A train journey of under 2h30 won't increase typical travel time as compared to a short-haul flight. For the short-haul flight, you need to reckon in that the airports are almost certainly going to be further from your starting point and your destination (meaning that you need to add in the travel time to and from the airports), as well as the fact that you tend to have to get to the airport two to three hours before the flight. Even for the Eurostar from London, where they have introduced airport-style security checks, you are recommended to get to St Pancras just 1h15 before departure - most other rail routes, you can arrive a few minutes before departure. And you get off the Eurostar at the Gare du Nord, no need to wait at the baggage claim, and you're within easy walking distance of Montmartre and many other sights of Paris, rather than 50 minutes outside Paris by taxi or train, if you'd arrived at Charles de Gaulle. As for "what if the train's late"... what if the plane's late? What if you don't make the flight due to queues at check-in? An anecdote isn't good evidence for the comparitive reliability of modes of different modes of transport.
I noted that the report was from researchers in Britain and Spain. No vested tourism interests here, no sirree! A more valid question might be about the strict necessity of such travel, rather than whether we can do it more efficiently.
@@janibeg3247 The ban is specifically for routes where there is an alternative train journey taking less than 2h30, as I understand it. I've just checked trains from Nice to CDG on the SNCF site - it wasn't showing any journeys under 2h30, so that route wouldn't be affected.
Also, regarding the formulas to determine shape reminds me of a retired NASA(I believe) engineer who got into Oragami and then invented a formula he could use to determine how to make ANY shape by folding. It was very interesting been a long time since I heard the interview with him.
The video insert shows the CO2 concentration in milligrams (mg) while the audio says it is micrograms (μg, sometimes mcg). The difference is a factor of 1000.
I think what this hypothesis actually DOES describe, as well as the initial excitement, is the mounting desperation to explain the dark energy problem in any way they can. There's been ZERO detections of anything outside the Standard Model in terms of particles, The scary possibility is that astrophysics measurements have a fundamental flaw no one has discovered yet, and that could be something simple that's been overlooked. A relativistic effect over time and distance no one considered or anticipated... OR that there IS a serious flaw in the entire Big Bang theory itself. And since no one has any other explanation, that would be a staggering blow.
Sabine: "They don't explain how black holes would give rise to this negative pressure." But they do? 5th paragraph in the introduction: "This has implications for singularity-free BH models, such as those with vacuum energy interiors (e.g., Gliner 1966; Dymnikova 1992; Chapline et al. 2002; Mazur & Mottola 2004; Lobo 2006; Mazur & Mottola 2015; Dymnikova & Galaktionov 2016; Posada 2017; Beltracchi & Gondolo 2019; Posada & Chirenti 2019)." Vacuum energy is material with P=-rho.
great show as usual. Nice formulation:" just taking your conclusion as an argument". One must admit that it at least sounds cool to have both "black holes" and "dark matter" in the same title of a paper. Sure will make headlines. And it makes so much sense ,as black holes clearly are dark ...
Hi Sabine, can't wait to hear from you about the newfound old galaxy that seem to be way too large for such a short period of time after the Big Bang !
Thank you. I read several articles on the topic and none of them explained the leap in logic from "The mass of black holes increases in relation to dark energy" to "Black holes are the source of dark energy." As usual, you debunk wild claims.
Even if it's just a minor saving on reducing the number of flights, it helps in changing the mindset with regard to flying distances for which other alternatives are available. It also helps in acquiring investments for these alternatives - making them more reliable, comfortable and affordable on the longer run. Personally I find train travel much more relaxed even if it takes longer. A train to Berlin takes me 7 hours city center to city center. Flying takes an hour, + ca 1.5h to get to and from airports, + 2 hours waiting at the airport if the lines are long (which they often are) - so also some 4.5h all in all. Sure, it's 2.5h more by train - but I have a more spatious seat and WIFI (so can actually work), and need to change trains only once. I'll take that any day.
I'm a frequent user of the Paris - Strasbourg TGV route (about 500 km) There are no more plane on that route (long before the ban) but if there was, here are my options : Train : 2h30 + 40 min to go to the station + 15 min to my destination in the city center + 20-40 min of margin to wait at the station Plane : 1h + 1h30 to go the airport + 40 min to my destination by bus, or 20 min with a taxi + 1h-1h30 of margin to wait at the airport, including eventually checking my luggage, security... Car : 5h, and nothing else I can do while concentrating on not dying behind the wheel (I sold the only car I've even own at the end of last century) Bus : 5h40 + 40 min go to the bus station + 20 min to my destination in the city center but I can read or play a video game at least These timings are why Air France killed that specific route : they could not compete on the total time. The bus can compete on price. The only reason I've use a car is to move my furniture.
No issue for local travel with no baggage but doesn't seem practical if you have baggage. No one is going to want to drag carts of luggage all over a train station.
@@RS-ls7mm Unless you carry multiple large carts of luggage (which doesn't seem all that common to me), traveling with luggage by train is very much feasible.
The short haul issue is an interesting one and must certainly be circumstantial. In New Zealand there is a route between Wellington and Blenheim. The turbo prop flight is just 15 minutes and I asked the pilot what the fuel consumption was which was from memory something like 340 litres for 45 passengers. The road route involves a ferry section and a mountainous drive with an all up travel time of some 3 hours if everything lined up. The plane fair was $NZ 100 so the airline made good money on that run and people saved a combined 120 hours. Also the skirt around the cost scenery was spectacular.
Fascinating! One little thing; CO2 emissions from aviation should be compared with CO2 emissions of the transport sector and not compared with the total CO2 emissions from energy generation, I think. So it is perhaps 10% and not merely 2 %. But this does not invalidate the finding that shorter distance flying is not an important culprit in the cockpit!
Sabina, you may be aware of the correlation between elderly falls and subsequent death. This, in fact, took my wife away last year. She fell on June 9. A sequence of bodily responses to the injury led to her hospitalization on June 29 with grand mal seizure. Subsequently, she died July 15. The exoboot, had she used such a thing, could have prevented the initial fall. By the way, she was 58.
In contemplating travel times, one must include the dead time at the departure airport and the landing airport, associated with parking, baggage handling, TSA scrutiny. For example, it takes 1 hour to fly from Seattle WA to Spokane WA in the USA, from wheels up to wheels down. However, however you will spend at least 3 hours in airports. This also does not include the time it takes to travel to/from each airport, nor the schedule availability of flights (*). It takes 5 hours to drive from Seattle to Spokane, and it is almost certainly more comfortable and less annoying to drive. Plane fare is approximately $100 per person. Gasoline is approximately $50 per *vehicle*, so my elderly minivan can get 4 people from Seattle to Spokane for about 1/8th the cost per person, and in about the same time. The dead time at airports is, however, a fixed cost, and does not vary with the distance travelled. It is certainly faster and more cost effective to fly from Seattle to NYC than it is to drive. If you are more sensitive to travel time, then the breakeven time corresponds to about 300 mi/500 km. If you are more sensitive to cost, then the breakeven distance is considerably greater; in fact, it is cheaper for two people to drive across the United States than to fly across the United States, if they share a car with decent fuel efficiency (say 25 mpg in our "freedom based" units). ----- One statistic that favors airlines: safety per traveller-mile. Modern air transportation is extremely safe compared to automobiles. (*) A few years ago I suddenly needed to travel from North Seattle WA to Couer d'Alene ID, in the USA. The travel distance was about 350 mi/500 km. By far the fastest option was to drive the route, by myself. It was also the least expensive option.
That clears up a lot of things for me. I think the blackhole coupling theory papers need a lot more research and observation. But if it turns out SMBHs are indeed gaining more mass than can be accounted for than from merger or accretion, then things could get interesting.
It could just be yet another exo-boob.. The idea of black holes destroying mass as well as attracting it makes a lot more sense to me, perhaps feeding on darkish matter (not necessarily a new particle, just a continuous but sparse mixture of ions end electrons we can't see).. mass destruction on a universe scale. I prefer the idea of black holes concentrating universe glue (that could just be matter) away from the rest of the universe. Perhaps both happen.
Fraser cains interview with the author of that paper is quite good, if you are interested. Sabine should watch it. Its far from certain, the authors know that and are not crackpots, but it is plausible. My 2 cents.
@@deltalima6703Thank you for the reference. This seems to be a topic that requires more information from the source on what was actually meant and less intermediate filtering. It seems like some necessary extra words were filtered out.
All i can think is that if the BH=DE idea, is that if it is correct, the mechanism must be somewhere outside our view of 4D spacetime. If there is such a place. :) I love the solar system analysis and classification. It does what science should. Breaking things down to their simplest form.
Another super interesting video, Sabine! Oh dear! The German rail system is a disaster! When every second train is cancelled, it does save carbon emissions, but sort of defeats the purpose of travel.
Interesting comments on how copper makes fuel. My questions regarding copper are 1) What is the current inventory of copper in the world? 2) How much copper would be required to produce a sufficient amount of fuel to really make a difference? 3) How much energy is consumed in the production of copper? 4) How much fuel is consumed in the production of the devices and machinery necessary to produce copper? 5) What is the net gain/loss in the production of fuel of this process? 6) What is the net effect on the environment?
@@Andrius319 We have the solutions for the wave equations. But this isn't the simple case. There are two problems. İt's hard to create exact boundary conditions practically. You need to consider more parameters. The other problem is that there are two different substances. Depending on the properties the waves could go through particles, could be reflected (particles create new waves) or a mix of both. Or let me say it like this, i know what i am talking about. I am not an expert, but at least i know how to solve wave equations with boundary conditions.
@@Andrius319 Oh are you talking about my second idea? Oh boy that's infinitely easier to solve. The particles are collected in the valleys of waves. So if we take a 2d surface that's not a big deal. İn 3d it gets a little harder.
Glad to see that someone else is showing some skepticism of the Black Holes = Dark Energy idea. I just heard Fraser Cain's interview with the guy who proposed it. Fraser gives it some minimal skepticism, but really the idea seems to be just correlation = causation.
Tehom: Which is why for such ideas, evidence from experiments is critical before the ideas are just accepted as true. And for some ideas like (as I understand it) superstring theory, it can be difficult to have good experiments to prove things.
I read two reviews about their paper, then tried to read the paper itself (I am not a cosmologist!). And yeah, that's how their paper starts, except they call it coupling, which sounds more tangible, so it must be true. Then leaps of logic, like black holes contain (some) vacuum energy, and someone years ago theorized vacuum energy black holes, and these "vacuum energy black holes" "couple" to the expansion of the universe, so: We have the answer!! I didn't see any evidence of a source of energy for all this, which is the real question behind dark energy. Where is this vacuum energy coming from, beyond what we already know, to make up ~ 75% of the total energy in the universe? Best I can figure is that there must be lots of vacuum energy black holes out there sweeping the cosmos and scooping up vacuum energy (while, somehow not draining off the energy of the universe, but somehow expanding it). Or maybe this new type of black hole just takes in regular stuff, converts it to vacuum energy, magically multiplies it, and output this multiplied energy as dark energy? Oh, did I mention that they state at the start that current models of the universe don't model the growth of black holes well - i.e., actual black holes are bigger than current models project. So they don't correlate ("couple") well to the expansion of the universe. Well, duh! That's a big surprise. Models that we know to be insufficient are actually insufficient when tested for insufficiency! My head was spinning after a couple of paragraphs. I concluded that this was all way over my head, or so off the wall that even a layperson could identify it as off the wall.
I found the video with an interview with the author, and my opinion has not improved. It's correlation, correlation all the way down, with no source mentioned. Comment the interviewee makes at the end "the universe is expanding, so dark energy is being created". Which amounts to saying "we don't know where dark energy is coming from". Ok, now their theory: We can't explain the growth of black holes. But that growth is highly correlated with the expansion of the universe, therefore with dark energy. So we propose that black holes are composed of dark energy (which at one point he says = vacuum energy). Basically, what goes into black holes gets converted to dark energy, no singularity at the core, deSitter space etc. So as black holes grow with this dark energy through this new type of core it feeds the expansion of the universe. So - we can't explain how black holes have gotten so big, but their size is correlated with expansion of the universe. But they never propose a source for how black holes got this big (which is essential for their theory to work). And it obviously a new complicated mechanism which destroys our current concept of black holes. And wait, black holes do all this (expand the universe with dark energy while still containing that energy and not getting any smaller)?? So they are a magical funnel duplicator which converts ordinary matter and energy to dark energy, duplicates it and expands the universe with it? Because, correlation?? (and yes he says correlation a lot - coupling was just a magic word used in the paper to make it sound more like a substantial thing). But please, go and watch that video interview yourselves, and reach your own conclusions: ua-cam.com/video/-8CIUzPkigQ/v-deo.html&ab_channel=FraserCain
You are already my favorite physicist. But the fact that you show Pluto as a planet orbiting the Sun, just makes me admire you more. Congratulations and thank you.
Some other considerations about switching short-haul flights to trains: It could reduce noise pollution by having fewer flights. Reduced flight volume could eliminate the need for building expensive new airports in regions whose airports are at capacity. Less crowded airports could improve the quality of life for people taking medium- and long-haul flights. Also the time savings for some short-haul flights is less than people might think when you take into account travel time to and from the airport and getting through security.
I love watching these just for the humour alone - thanks for this approach to talking about physics, I learn a lot. I look a bit silly laughing while watching at the gym on the treadmill, but what the hell.
Holy crap! I have no formal science education, but I have independently considered that the effects of dark energy might result from the curvature of empty space over large distances. Of course, being a layman, I also acknowledge that I know very little about the topic, so I have never shared my thoughts with anyone. Now, after hearing Sabine suggest that this is the most plausible explanation for our observations, I feel like a little genius. Thank you, Sabine, for creating awesome content that confirms my beliefs! ❤
I read this in an Astronomy 101 book; the order of the planets as we see them today is NOT the same order they were formed at. I forgot what formed where, but it's counterintuitive! I think it was either Jupiter or Uranus that was closer to the sun than the Earth is today. It blew my mind! 🤯
I originally thought your synopsis of current science would be a waste of time when you first began. I am a big fan of your single topic discussions on the weekend. This is the first entire episode in this format, I have watched, and I found it very informative. So this proves my initial thoughts were wrong and yours were spot on. So count me in on being a weekly viewer. Your main topic on the Dark Energy was what intrigued me. I had already watched another presentation by another physicist and was rather skeptical of the idea myself. I now know sometimes my thoughts are the correct ones but it is looking like I am only correct when my thoughts agree with Sabine!!!
Yeah the dark energy idea becomes even more pathetic when we look at the other observations which challenge the standard model of cosmology using actual observations and an experimental falsification test constructed by Elis and Baldwin 1984. The test is simple in that if the CMB dipole is purely kinematic which is necessary for the CMB dipole to not falsify any and all forms of the cosmological principal within the observable universe then the dipole on the sky for cosmologically distant sources (i.e. after removing local clustering effects) should be identical to that of the CMB regardless of its actual distance. If you have followed this channel for a while you might remember that this was tested by Nathan Secrest et al 2021 using 1.36 million quasars and shown to be more than twice the magnitude of the CMB dipole and thus a 4.9 sigma discrepancy with less than a 1 in 2 million odds of being a statistical fluke. If you saw the results a few weeks ago independent analysis has now verified the results and moreover consequently raised the discrepancy to 5.7 sigma significance. This matters because independent work has long shown that the measurements attributed to "dark energy" are trivially inevitable within any initially expanding and sufficiently large inhomogeneous and anisotropic solutions to the Einstein field equations. Thus by allowing the metric to evolve without artificial constraints of linearity to the allowable behavior of the Einstein field equations made for reasons of convenience we can completely eliminate the whole "dark energy" component in a manner similar to how allowing orbits to be elliptical in a heliocentric frame allowed one to naturally reproduce observed planetary motions without the need of multiple epicycles to force fit geocentric models to observations. And that is moreover before you factor in all the other "crises in cosmology" that have gotten ignored like the axis of evil alignment of the CMB dipole with the higher multipoles (quadrupole, octupole etc.), the Hubble tension, the now many dozens of structures in the universe to large to exist under the current cosmological model, observational constraints on the assembly of the local group incompatible with the standard cosmological model of cosmology, or the actual fing Einstein field equations which if analyzed thoroughly have been mathematically proven that in an initially expanding universe the cosmological principal is mathematically invalid due to requiring logical and or causal violations,(or in simpler words you can't make any mathematically valid nontrivial model where large scale isotropy is preserved but local structure is allowed to form as no such solutions exist within the set of all possible solutions to the full Einstein field equations). I could go on but really I just wanted to point out there is a huge and ever growing number of reasons to doubt the validity of the whole cosmological standard model. For example in denser regions of spacetime you will naturally get more redshift from the perspective of a distant observer independent of the distance hence both of the observed correlations can be explained fairly trivially if you look at the actual theory of general relativity instead of the drastically simplified through a questionable lack of logic and wishful thinking where one assumes that such over densities and underdensities should average out. (That argument also would predict that strong gravitational lensing of clusters of galaxies is impossible just to point out the fallacious nature of such an argument)
I used to work for a LARGE aircraft manufacturer. One unintended consequence of short hauls is they shorten the life of the plane's skin rivets. It isn't time that is the problem it is the number of cycles. When an airplane goes to altitude the higher pressure inside than outside causes the plane to expand and then when it comes down, the plane contracts. The rivets can only go through this so many times before the plane is worn out and either has to be replaced or have all of the skin rivets replaced or the plane gets replaced all together. Either way the carbon foot print of the plane just got a lot bigger. Some planes are not designed to be suitable for all of the skin rivets to be replaced. Those get sold to South American or African airlines that don't care so much about safety margins.
The downsides of trains are extremely easy to solve if companies can communicate with each other. Connecting flights are already a thing, extending it to trains is easy to enforce. Also, airlines are some of the worst companies when it comes to passenger service. Any move away from them is a blessing in the long term.
Sabine, check out!! there was once a Soviet phycisyst who proposed that black holes would be something completely different than what current theories suggest, and that they would indeed have negative pressure on the inside. This negative pressure wouldn't be perceptible on short distances (gravity would win here, behaving as "classic" black holes) but after some threshold this would indeed have the effect of pushing upon space, leading over time to the expansion of universe. If I recall it correctly, his theory was the "gravastar" because these would really be stars made up of pure gravity or something like that - seeing this paper immediately reminded me of this man's theories, and how sicely it fits them.
The hypothesis that "the universe is made up of 100% dark humor" goes a VERY long way to explain much of my life. I, for one, think you're on to something!
I was looking this new series of Bryan Cranston, Your Honor, u know, the guy from Breaking Bad and Malcolm. I stopped it, this is always better than anything else 🤯
The abbreviation "mg" generally stands for milligrams but in the video you said micrograms when talking about the concentration of carbon dioxide. Could you clarify which amount is correct?
Excellent weekly shows! It really takes a great deal of real energy to pump out weekly shows and keep them fun & Interesting. Might be off scientific topic but Sabine is really cute!
How is travel time calculated? I doubt you can save a lot of time from a short haul flight compared to taking a train if you include transport time to and from airports and check-in time.
Thank you! I listened to one of the authors of the black hole / Dark energy paper on Fraiser Cain's channel and found it fascinating . Was I convinced of a ground breaking discovery? No, but interesting ideas presented.
Fraser is "interesting". One the one hand, he presents professionally and has impressively deep knowledge of his topic. On the other hand, he seems easily taken in by new ideas. The wonderful YT algorithm offered that video to me but I thought "not likely" and gave it a miss. Each to their own.
@@AndrewBlucher When talking about a 100+ year old problem that no one has even an inkling of an idea of how to solve, discarding new ideas will never get you an answer.
@@BenjaminCronce Which 100+ year old problem is that? Dark matter can be traced 1933, dark energy to 1998. People come up with new ideas all the time. The questions they need to answer are what is the mechanism, is it testable, does it make predictions? Take string theory. Has it actually produced any results? Apart from beautiful math and lots of papers?
9:31 planes can be delayed too. In most countries they are even more often delayed than trains, especially if you count longer delays (delays under 1 hour are not that relevant because in this case passengers usually have enough margins to still get their connecting flight).
Sabine, when you say "micrograms per liter" and the visual shows "mg/L" is that a typo, or does Germany use a different abbreviation for micro than the US does? I'm accustomed to seeing microgram being abbreviated "ug" (using mu if available on the keyboard, or lowercase U if it isn't). In the US, mg is "milligram" and mcg is commonly used by pharmacists for "microgram". Thanks if you can clear this up.
Totally with you on synthetic hydrocarbons for hard-to-decarbonise uses!! Have been saying this for years but I don’t have quite the same platform. 🙂 Long-haul air travel being a perfect example!
I would not say that it is underexplored, though. The problem is efficiency, where the direct use of electricity and even green hydrogen, in some cases even the use of natural gas, are still with a much lower CO2 footprint. I agree. This can only be a solution for very hard-to-decarbonize areas. I would go as far as to say that short haul air travel will be electrified in the next decade.
Sure. I wonder how much energy it will take and how much seawater must be processed to take 20 billion tons of CO2 out of the oceans every year, and then turn it into dry ice, and then sequester that ice underground somewhere forever.
what happens with the copper? does it oxidize in the process are we using up a rare metal that we have shortages of to produce fuel for a little longer or is the copper unharmed and possible to be used indefinitely this kinda sounds like just pushing the problem forward, pushing it forward with something already in short supply causing two shortages instead of one
@@WeighedWilson we have no perfect energy transfer we use energy to make a fuel to produce less energy that we then can dump in energy to make the resource back the transition would be a loss we dont have excess to dump into a loss no, rust is gone in practical terms
The paper regarding the evidence for cosmological coupling of black holes is super exciting. This could easily be the most important discovery in cosmology this century. I’m looking forward to the many many papers that will be published over the next few years as everyone digs deeper into this.
I'm super excited to defeat the local curvature of spacetime's efforts to mess with my ankles by lying on my sofa. The methode champagne's a great excitement magnifier too.
to me it sounds quite plausible that black holes influence the curvature of space in a way that is consistent with the cosmological constant. i aggree though that the name dark energy is a bit misleading
7:10 I don't get why solar systems like ours are the least common, when it looks from the graph like they are the second most observed. Are the models trusted more than the observations?
Could you discuss thorium reactors. Some people think that they will solve all our energy problems. I have not heard a careful and not biased discussion.
@@SabineHossenfelder Thanks for your response. I am interested in more details about thorium reactors. They say that they cannot be used to make a bomb, why? They say that can't be used to make a dirty bomb, why? That thorium reactors are safer in emergency situations, why? An end of life thorium reactor is easier to deal with, why? The isotopes produced in thorium reactors have shorter half-lives, is this true? I know that thorium was not of military use in the 1940's so research and development was not funded. Is this the only reason that we don't use thorium today? It seems that there are only thorium enthusiasts and everyone else who ignore them. Thus, no detailed discussion.
An apparent increase in mass of very old objects is something I would expect from GR. Specifically, if you think of gravity in terms of time dilation instead of potential, the manifold's curvature into the time dimension should increase over time regardless of whether the object is accreting new mass just because time ticks more slowly the deeper you go in the gravity well. As you evolve the manifold (defined as all points with proper time equidistant from the origin) forward in time, the parts deep in the well will continually lag behind. That it's connected specifically to the general rate of growth of the universe should be expected since gravitational collapse can be seen as a consequence of expansion or vice versa in a closed thermodynamic expansion model.
@@tonywells6990 A more intuitive way of thinking about this is that it has more to do with the observations which are used to infer indirectly the mass of the black hole based on the Doppler shift period of material accreting onto and or orbiting around it. If the rate of time passing is slowed down by local time dilation then you will observe a broadened spectrum suggesting that the distance of the accretion disk and thus consequently the mass of the black hole is larger than it would otherwise be. Hence the black hole appears to be more massive (and older if we assume all the observed redshift is purely due to distance rather than partly due to curvature of spacetime) to a distant observer than would otherwise be expected.
The black hole thing has always interested me. I mean, if space is expanding outside of black holes, wouldn't it be expanding inside the black holes as well?
As Guy correctly says, whether or not an object expands with the universe depends on how strongly it is held together by gravity. Black holes are held together too strongly, they don't expand. Neither do, for that matter, stars or planets or atoms.
By definition, black holes don't grow. They are singularities. The event horizon of a black hole does grow as it's gravity increases but the black hole itself is infinitely small no matter how much stuff it eats.
Thank you very much for your succint recap of the news! Can you please provide links to the research? I am particularly interested in '3D printing wiht sound' paper.
Your friends are richer than you today because they have a key that you don't have and that key is good investment, build your income now and be part of the big guns in today's economy.
l agree with you mate. Investing is the key to maintaining your financial longevity. And not just any investment but an investment with guaranteed profitability.
@@economistasincero2780 My investment manager is Mrs Jennifer Allen , she is an expert when it comes to investing that produces a good percentage profit rate.
Watching Sabine’s weekly commentaries I am assured that cosmology still holds many more contradictions and unresolved questions than our wishfully advanced knowledge would hope.
Okay, longer "travel times" when you take a train instead of a short-haul flight, but you also don't waste a lot of time travelling to the city outskirts to get to the airport, get through security, get on your plane, get off the plane, claim your luggage, get out of the airport, get back into the city you want to go to. If you take a train, you probably go to the city centre, get on the train, get off the train, and you are directly in the city. That of course doesn't mean that rail services can be vastly improved in Germany, but a lot of people seem to ignore all of this extra time before and after the actual travelling part of the trip.
???? Why would you multiply all the percentages? 33% are short haul flights (even if 1500km is arbitrary). It is irrelevant if they are domestic or international. It is also irrelevant if they are also carrying only passengers, or only carrying freight or a combination. The goal is to encourage a more carbon neutral method of transport. Not all trains are run on diesel, or by coal-fired electricity as in Germany.... Further, if you look at the original source you can read that the 2.4% of global CO2 emissions in 2018 from fossil fuel use is a 32% increase over the previous five years. Further, this emissions growth rate is 70% higher than assumed under current ICAO projections. As covid bans are now lifted, we can expect more travel.
Sabine is definitely made 100% of dark humor...
The best kind, I'm sure.
And I like dark humour.
Dark German chocolate, I would say.
Kind of dark, kind of light. She is in superposition.
She needs to put that on a tshirt or hoodie!
A train journey of under 2h30 won't increase typical travel time as compared to a short-haul flight. For the short-haul flight, you need to reckon in that the airports are almost certainly going to be further from your starting point and your destination (meaning that you need to add in the travel time to and from the airports), as well as the fact that you tend to have to get to the airport two to three hours before the flight.
Even for the Eurostar from London, where they have introduced airport-style security checks, you are recommended to get to St Pancras just 1h15 before departure - most other rail routes, you can arrive a few minutes before departure. And you get off the Eurostar at the Gare du Nord, no need to wait at the baggage claim, and you're within easy walking distance of Montmartre and many other sights of Paris, rather than 50 minutes outside Paris by taxi or train, if you'd arrived at Charles de Gaulle.
As for "what if the train's late"... what if the plane's late? What if you don't make the flight due to queues at check-in? An anecdote isn't good evidence for the comparitive reliability of modes of different modes of transport.
I noted that the report was from researchers in Britain and Spain. No vested tourism interests here, no sirree! A more valid question might be about the strict necessity of such travel, rather than whether we can do it more efficiently.
fly from Nice to CDG (Paris) to make a flight to elsewhere - a great time and effort saver
@@janibeg3247 The ban is specifically for routes where there is an alternative train journey taking less than 2h30, as I understand it. I've just checked trains from Nice to CDG on the SNCF site - it wasn't showing any journeys under 2h30, so that route wouldn't be affected.
@@robhogg68 thank goodness
Such an excellent review of current topics. Thank you.
Summarized only the most important, add some examples, put two jokes and you have a masterpiece. hat a pleasure to listen to you.
I appreciate your sense of humour, thanks!
Its german, similar to elons actually.
Also, regarding the formulas to determine shape reminds me of a retired NASA(I believe) engineer who got into Oragami and then invented a formula he could use to determine how to make ANY shape by folding. It was very interesting been a long time since I heard the interview with him.
I remember seeing a video about this guy. It was quite fascinating.
That process reminds me of Buckminster Fuller's engineering work.
About 20 years ago I went back to Pasadena to visit (as a Caltech grad), and I met an origami group who followed that.
The video insert shows the CO2 concentration in milligrams (mg) while the audio says it is micrograms (μg, sometimes mcg). The difference is a factor of 1000.
As soon as I heard about the black hole/dark energy relationship evidence, I've been waiting to hear your opinion before I get excited about it.
I think what this hypothesis actually DOES describe, as well as the initial excitement, is the mounting desperation to explain the dark energy problem in any way they can. There's been ZERO detections of anything outside the Standard Model in terms of particles,
The scary possibility is that astrophysics measurements have a fundamental flaw no one has discovered yet, and that could be something simple that's been overlooked. A relativistic effect over time and distance no one considered or anticipated... OR that there IS a serious flaw in the entire Big Bang theory itself. And since no one has any other explanation, that would be a staggering blow.
I love your videos! These ones help me feel up to date on what's going on in the science community.
These people are morons chasing unicorn farts. But hey, whatever makes you feel good.
Sabine: "They don't explain how black holes would give rise to this negative pressure."
But they do? 5th paragraph in the introduction:
"This has implications for singularity-free BH models, such as those with vacuum energy interiors (e.g., Gliner 1966; Dymnikova 1992; Chapline et al. 2002; Mazur & Mottola 2004; Lobo 2006; Mazur & Mottola 2015; Dymnikova & Galaktionov 2016; Posada 2017; Beltracchi & Gondolo 2019; Posada & Chirenti 2019)."
Vacuum energy is material with P=-rho.
Thank you for the news.
great show as usual. Nice formulation:" just taking your conclusion as an argument". One must admit that it at least sounds cool to have both "black holes" and "dark matter" in the same title of a paper. Sure will make headlines. And it makes so much sense ,as black holes clearly are dark ...
Thanks for all the news, Sabine! 😊
Stay safe there with your family! 🖖😊
What a delicious sense of humor you have,Sabine. I enjoy your videos as they are so informative and I learn so much,thank you!
Hi Sabine, can't wait to hear from you about the newfound old galaxy that seem to be way too large for such a short period of time after the Big Bang !
Thank you. I read several articles on the topic and none of them explained the leap in logic from "The mass of black holes increases in relation to dark energy" to "Black holes are the source of dark energy." As usual, you debunk wild claims.
Even if it's just a minor saving on reducing the number of flights, it helps in changing the mindset with regard to flying distances for which other alternatives are available. It also helps in acquiring investments for these alternatives - making them more reliable, comfortable and affordable on the longer run.
Personally I find train travel much more relaxed even if it takes longer. A train to Berlin takes me 7 hours city center to city center. Flying takes an hour, + ca 1.5h to get to and from airports, + 2 hours waiting at the airport if the lines are long (which they often are) - so also some 4.5h all in all.
Sure, it's 2.5h more by train - but I have a more spatious seat and WIFI (so can actually work), and need to change trains only once. I'll take that any day.
I'm a frequent user of the Paris - Strasbourg TGV route (about 500 km)
There are no more plane on that route (long before the ban) but if there was, here are my options :
Train : 2h30 + 40 min to go to the station + 15 min to my destination in the city center + 20-40 min of margin to wait at the station
Plane : 1h + 1h30 to go the airport + 40 min to my destination by bus, or 20 min with a taxi + 1h-1h30 of margin to wait at the airport, including eventually checking my luggage, security...
Car : 5h, and nothing else I can do while concentrating on not dying behind the wheel (I sold the only car I've even own at the end of last century)
Bus : 5h40 + 40 min go to the bus station + 20 min to my destination in the city center but I can read or play a video game at least
These timings are why Air France killed that specific route : they could not compete on the total time. The bus can compete on price. The only reason I've use a car is to move my furniture.
No issue for local travel with no baggage but doesn't seem practical if you have baggage. No one is going to want to drag carts of luggage all over a train station.
@@RS-ls7mm Unless you carry multiple large carts of luggage (which doesn't seem all that common to me), traveling with luggage by train is very much feasible.
@@toomanycharacter At my age, that's not a reasonable expectation.
Good for you. Not everyone shares your preferences and they shouldn’t be forced.
The short haul issue is an interesting one and must certainly be circumstantial. In New Zealand there is a route between Wellington and Blenheim. The turbo prop flight is just 15 minutes and I asked the pilot what the fuel consumption was which was from memory something like 340 litres for 45 passengers. The road route involves a ferry section and a mountainous drive with an all up travel time of some 3 hours if everything lined up. The plane fair was $NZ 100 so the airline made good money on that run and people saved a combined 120 hours. Also the skirt around the cost scenery was spectacular.
That's not what is being proposed. Where there is an existing rail link it makes more sense to sweat that asset. E.g. WLG to PMR
Great content. I like your insights. I have been following for about 3 years and have learned quite a lot. Thanks.
Fascinating! One little thing; CO2 emissions from aviation should be compared with CO2 emissions of the transport sector and not compared with the total CO2 emissions from energy generation, I think. So it is perhaps 10% and not merely 2 %. But this does not invalidate the finding that shorter distance flying is not an important culprit in the cockpit!
The universe is indeed made up of “dark humor”!! 😊
it matters.
Everything is irrelevant just like Douglas Adams says.
That explains everything. 😁
Dark humor is like food: not everyone gets it.
@@janerikrasmussen Would you say its a "theory of everything" then? :)
Sabina, you may be aware of the correlation between elderly falls and subsequent death. This, in fact, took my wife away last year. She fell on June 9. A sequence of bodily responses to the injury led to her hospitalization on June 29 with grand mal seizure. Subsequently, she died July 15. The exoboot, had she used such a thing, could have prevented the initial fall. By the way, she was 58.
Thank you for another really fascinating video! This channel really makes me think.
In contemplating travel times, one must include the dead time at the departure airport and the landing airport, associated with parking, baggage handling, TSA scrutiny.
For example, it takes 1 hour to fly from Seattle WA to Spokane WA in the USA, from wheels up to wheels down. However, however you will spend at least 3 hours in airports. This also does not include the time it takes to travel to/from each airport, nor the schedule availability of flights (*).
It takes 5 hours to drive from Seattle to Spokane, and it is almost certainly more comfortable and less annoying to drive. Plane fare is approximately $100 per person. Gasoline is approximately $50 per *vehicle*, so my elderly minivan can get 4 people from Seattle to Spokane for about 1/8th the cost per person, and in about the same time.
The dead time at airports is, however, a fixed cost, and does not vary with the distance travelled. It is certainly faster and more cost effective to fly from Seattle to NYC than it is to drive.
If you are more sensitive to travel time, then the breakeven time corresponds to about 300 mi/500 km. If you are more sensitive to cost, then the breakeven distance is considerably greater; in fact, it is cheaper for two people to drive across the United States than to fly across the United States, if they share a car with decent fuel efficiency (say 25 mpg in our "freedom based" units).
-----
One statistic that favors airlines: safety per traveller-mile. Modern air transportation is extremely safe compared to automobiles.
(*) A few years ago I suddenly needed to travel from North Seattle WA to Couer d'Alene ID, in the USA. The travel distance was about 350 mi/500 km. By far the fastest option was to drive the route, by myself. It was also the least expensive option.
That clears up a lot of things for me. I think the blackhole coupling theory papers need a lot more research and observation. But if it turns out SMBHs are indeed gaining more mass than can be accounted for than from merger or accretion, then things could get interesting.
this maybe universal to all bodies in the universe, if the expanding earth hypothesis holds some weight under certain conditions.
It could just be yet another exo-boob.. The idea of black holes destroying mass as well as attracting it makes a lot more sense to me, perhaps feeding on darkish matter (not necessarily a new particle, just a continuous but sparse mixture of ions end electrons we can't see).. mass destruction on a universe scale. I prefer the idea of black holes concentrating universe glue (that could just be matter) away from the rest of the universe. Perhaps both happen.
Fraser cains interview with the author of that paper is quite good, if you are interested. Sabine should watch it.
Its far from certain, the authors know that and are not crackpots, but it is plausible. My 2 cents.
@@deltalima6703Thank you for the reference. This seems to be a topic that requires more information from the source on what was actually meant and less intermediate filtering. It seems like some necessary extra words were filtered out.
@@deltalima6703 Sabine should NOT watch it. She's read the paper and has given you her conclusion.
We love you, Sabina. You convey the material in a clear way and are ballsy and funny. 💪
All i can think is that if the BH=DE idea, is that if it is correct, the mechanism must be somewhere outside our view of 4D spacetime. If there is such a place. :)
I love the solar system analysis and classification. It does what science should. Breaking things down to their simplest form.
Another super interesting video, Sabine!
Oh dear! The German rail system is a disaster! When every second train is cancelled, it does save carbon emissions, but sort of defeats the purpose of travel.
"Technical problems" and a string of cancelled trains is why I ended up driving from Freiburg to Itzehoe. Complete bollocks!
@@rallymaniac92 My favourite is "due to delays in the operational process..." - we are late because we are late :D
Interesting comments on how copper makes fuel. My questions regarding copper are 1) What is the current inventory of copper in the world? 2) How much copper would be required to produce a sufficient amount of fuel to really make a difference? 3) How much energy is consumed in the production of copper? 4) How much fuel is consumed in the production of the devices and machinery necessary to produce copper? 5) What is the net gain/loss in the production of fuel of this process? 6) What is the net effect on the environment?
So good, as always! At 18:24 you say micrograms but is written mg, and that is miligrams.
Here, here ! ✔
That ordered planetary systems are the least common aligns nicely with predictions of the Great Filter counter to the Fermi paradox.
I had the same idea with sound. But later, I thought it is only good to move small particles. It is really amazing what they did.
A similar technique works with photons.
i can imagine how difficult it is to form correct soundwave patterns in environment with forming object.
@@Andrius319 Quite!
It takes extremely complex 4D applied mathematics.
It is simplified that one does not require the relativistic dimension.
@@Andrius319 We have the solutions for the wave equations.
But this isn't the simple case. There are two problems.
İt's hard to create exact boundary conditions practically. You need to consider more parameters.
The other problem is that there are two different substances. Depending on the properties the waves could go through particles, could be reflected (particles create new waves) or a mix of both.
Or let me say it like this, i know what i am talking about. I am not an expert, but at least i know how to solve wave equations with boundary conditions.
@@Andrius319 Oh are you talking about my second idea?
Oh boy that's infinitely easier to solve. The particles are collected in the valleys of waves. So if we take a 2d surface that's not a big deal. İn 3d it gets a little harder.
Skepticism is the key to accuracy, and I'm glad to see you and Dr. Becky being skeptical of the black holes are dark energy idea.
Glad to see that someone else is showing some skepticism of the Black Holes = Dark Energy idea. I just heard Fraser Cain's interview with the guy who proposed it. Fraser gives it some minimal skepticism, but really the idea seems to be just correlation = causation.
They're right they're just looking at the wrong back holes. We need better gravitational wave visibility to solve this.
Tehom: Which is why for such ideas, evidence from experiments is critical before the ideas are just accepted as true.
And for some ideas like (as I understand it) superstring theory, it can be difficult to have good experiments to prove things.
I read two reviews about their paper, then tried to read the paper itself (I am not a cosmologist!). And yeah, that's how their paper starts, except they call it coupling, which sounds more tangible, so it must be true. Then leaps of logic, like black holes contain (some) vacuum energy, and someone years ago theorized vacuum energy black holes, and these "vacuum energy black holes" "couple" to the expansion of the universe, so: We have the answer!! I didn't see any evidence of a source of energy for all this, which is the real question behind dark energy. Where is this vacuum energy coming from, beyond what we already know, to make up ~ 75% of the total energy in the universe? Best I can figure is that there must be lots of vacuum energy black holes out there sweeping the cosmos and scooping up vacuum energy (while, somehow not draining off the energy of the universe, but somehow expanding it). Or maybe this new type of black hole just takes in regular stuff, converts it to vacuum energy, magically multiplies it, and output this multiplied energy as dark energy?
Oh, did I mention that they state at the start that current models of the universe don't model the growth of black holes well - i.e., actual black holes are bigger than current models project. So they don't correlate ("couple") well to the expansion of the universe. Well, duh! That's a big surprise. Models that we know to be insufficient are actually insufficient when tested for insufficiency!
My head was spinning after a couple of paragraphs. I concluded that this was all way over my head, or so off the wall that even a layperson could identify it as off the wall.
I found the video with an interview with the author, and my opinion has not improved. It's correlation, correlation all the way down, with no source mentioned. Comment the interviewee makes at the end "the universe is expanding, so dark energy is being created". Which amounts to saying "we don't know where dark energy is coming from". Ok, now their theory:
We can't explain the growth of black holes. But that growth is highly correlated with the expansion of the universe, therefore with dark energy. So we propose that black holes are composed of dark energy (which at one point he says = vacuum energy). Basically, what goes into black holes gets converted to dark energy, no singularity at the core, deSitter space etc. So as black holes grow with this dark energy through this new type of core it feeds the expansion of the universe.
So - we can't explain how black holes have gotten so big, but their size is correlated with expansion of the universe. But they never propose a source for how black holes got this big (which is essential for their theory to work). And it obviously a new complicated mechanism which destroys our current concept of black holes. And wait, black holes do all this (expand the universe with dark energy while still containing that energy and not getting any smaller)?? So they are a magical funnel duplicator which converts ordinary matter and energy to dark energy, duplicates it and expands the universe with it? Because, correlation?? (and yes he says correlation a lot - coupling was just a magic word used in the paper to make it sound more like a substantial thing).
But please, go and watch that video interview yourselves, and reach your own conclusions:
ua-cam.com/video/-8CIUzPkigQ/v-deo.html&ab_channel=FraserCain
You are already my favorite physicist. But the fact that you show Pluto as a planet orbiting the Sun, just makes me admire you more. Congratulations and thank you.
Bruh, it's just a big rock, no need to get attached to it 17 years after it was reclassified
@@Lucas__C nope justice for Pluto 😂. Make Pluto planet again.
She needs to do herself a favor though, tell MAGA Muskrat to lose her number, him calling her all the time isn't a good look.
So you mean, the status of Pluto is another sign for her rebellious mind? I have to think about it
@@michaelfried3123 ?, Yo what?, I am not even from USA. That was just a Pluto joke.
It would be really helpful if the studies referenced in these videos would be linked in the video description.
Try her newsletter. I am guessing that they are referenced there.
Some other considerations about switching short-haul flights to trains: It could reduce noise pollution by having fewer flights. Reduced flight volume could eliminate the need for building expensive new airports in regions whose airports are at capacity. Less crowded airports could improve the quality of life for people taking medium- and long-haul flights. Also the time savings for some short-haul flights is less than people might think when you take into account travel time to and from the airport and getting through security.
I love watching these just for the humour alone - thanks for this approach to talking about physics, I learn a lot. I look a bit silly laughing while watching at the gym on the treadmill, but what the hell.
0:51 Gotta love the centrism of calling the 4% slice "normal"! 😉
Holy crap! I have no formal science education, but I have independently considered that the effects of dark energy might result from the curvature of empty space over large distances. Of course, being a layman, I also acknowledge that I know very little about the topic, so I have never shared my thoughts with anyone. Now, after hearing Sabine suggest that this is the most plausible explanation for our observations, I feel like a little genius.
Thank you, Sabine, for creating awesome content that confirms my beliefs! ❤
Just imagine the halt modern physics is at, when the great latest physics news, are so obvious science, that the everyday man can predict.
I read this in an Astronomy 101 book; the order of the planets as we see them today is NOT the same order they were formed at. I forgot what formed where, but it's counterintuitive! I think it was either Jupiter or Uranus that was closer to the sun than the Earth is today. It blew my mind! 🤯
I originally thought your synopsis of current science would be a waste of time when you first began. I am a big fan of your single topic discussions on the weekend. This is the first entire episode in this format, I have watched, and I found it very informative. So this proves my initial thoughts were wrong and yours were spot on. So count me in on being a weekly viewer. Your main topic on the Dark Energy was what intrigued me. I had already watched another presentation by another physicist and was rather skeptical of the idea myself. I now know sometimes my thoughts are the correct ones but it is looking like I am only correct when my thoughts agree with Sabine!!!
Yeah the dark energy idea becomes even more pathetic when we look at the other observations which challenge the standard model of cosmology using actual observations and an experimental falsification test constructed by Elis and Baldwin 1984. The test is simple in that if the CMB dipole is purely kinematic which is necessary for the CMB dipole to not falsify any and all forms of the cosmological principal within the observable universe then the dipole on the sky for cosmologically distant sources (i.e. after removing local clustering effects) should be identical to that of the CMB regardless of its actual distance.
If you have followed this channel for a while you might remember that this was tested by Nathan Secrest et al 2021 using 1.36 million quasars and shown to be more than twice the magnitude of the CMB dipole and thus a 4.9 sigma discrepancy with less than a 1 in 2 million odds of being a statistical fluke. If you saw the results a few weeks ago independent analysis has now verified the results and moreover consequently raised the discrepancy to 5.7 sigma significance.
This matters because independent work has long shown that the measurements attributed to "dark energy" are trivially inevitable within any initially expanding and sufficiently large inhomogeneous and anisotropic solutions to the Einstein field equations. Thus by allowing the metric to evolve without artificial constraints of linearity to the allowable behavior of the Einstein field equations made for reasons of convenience we can completely eliminate the whole "dark energy" component in a manner similar to how allowing orbits to be elliptical in a heliocentric frame allowed one to naturally reproduce observed planetary motions without the need of multiple epicycles to force fit geocentric models to observations.
And that is moreover before you factor in all the other "crises in cosmology" that have gotten ignored like the axis of evil alignment of the CMB dipole with the higher multipoles (quadrupole, octupole etc.), the Hubble tension, the now many dozens of structures in the universe to large to exist under the current cosmological model, observational constraints on the assembly of the local group incompatible with the standard cosmological model of cosmology, or the actual fing Einstein field equations which if analyzed thoroughly have been mathematically proven that in an initially expanding universe the cosmological principal is mathematically invalid due to requiring logical and or causal violations,(or in simpler words you can't make any mathematically valid nontrivial model where large scale isotropy is preserved but local structure is allowed to form as no such solutions exist within the set of all possible solutions to the full Einstein field equations).
I could go on but really I just wanted to point out there is a huge and ever growing number of reasons to doubt the validity of the whole cosmological standard model.
For example in denser regions of spacetime you will naturally get more redshift from the perspective of a distant observer independent of the distance hence both of the observed correlations can be explained fairly trivially if you look at the actual theory of general relativity instead of the drastically simplified through a questionable lack of logic and wishful thinking where one assumes that such over densities and underdensities should average out. (That argument also would predict that strong gravitational lensing of clusters of galaxies is impossible just to point out the fallacious nature of such an argument)
You are both wrong. Sabine has been wrong about many things...
The best science news channel! Thank you!
Just want to say thank-you Sabine for your hard work in explaining so much good stuff to us all!
I love the way you cover all of latest scientific ideas Sabine, and the humour is great, keep up the good work 👍👍
Expectedly clear explanation!
I used to work for a LARGE aircraft manufacturer. One unintended consequence of short hauls is they shorten the life of the plane's skin rivets. It isn't time that is the problem it is the number of cycles. When an airplane goes to altitude the higher pressure inside than outside causes the plane to expand and then when it comes down, the plane contracts. The rivets can only go through this so many times before the plane is worn out and either has to be replaced or have all of the skin rivets replaced or the plane gets replaced all together. Either way the carbon foot print of the plane just got a lot bigger.
Some planes are not designed to be suitable for all of the skin rivets to be replaced. Those get sold to South American or African airlines that don't care so much about safety margins.
The downsides of trains are extremely easy to solve if companies can communicate with each other. Connecting flights are already a thing, extending it to trains is easy to enforce.
Also, airlines are some of the worst companies when it comes to passenger service. Any move away from them is a blessing in the long term.
Sabine, check out!! there was once a Soviet phycisyst who proposed that black holes would be something completely different than what current theories suggest, and that they would indeed have negative pressure on the inside. This negative pressure wouldn't be perceptible on short distances (gravity would win here, behaving as "classic" black holes) but after some threshold this would indeed have the effect of pushing upon space, leading over time to the expansion of universe. If I recall it correctly, his theory was the "gravastar" because these would really be stars made up of pure gravity or something like that - seeing this paper immediately reminded me of this man's theories, and how sicely it fits them.
Love your analysis and clear concise explanations! New subscriber.
It’s so refreshing to hear you mention the true issue with fuels: the fossil part.
I’m so annoyed with people yammering about cow farts.
"100% Dark Humor", I'm stealing that. Thank you.
What a great smorgasbord of topics this week. Thanks very much.
18:20 "mg/L" is milligram per liter, correct? Sabine said "microgram".
yay, Sabine read my mind! Exactly what i wanted to hear about!
The hypothesis that "the universe is made up of 100% dark humor" goes a VERY long way to explain much of my life. I, for one, think you're on to something!
Great post Sabine. I always enjoy tuning into your newest post. I particularly appreciate the absence of gobbledygook. Thank you so much.
Sabine, yours is the ONLY channel I ever subscibed to on UA-cam, just did. Your way is just unique!
I was looking this new series of Bryan Cranston, Your Honor, u know, the guy from Breaking Bad and Malcolm. I stopped it, this is always better than anything else 🤯
The abbreviation "mg" generally stands for milligrams but in the video you said micrograms when talking about the concentration of carbon dioxide. Could you clarify which amount is correct?
There's actually some pretty good news this week :)
"100% Dark Humour"
Your best one yet, Sabine!!
Excellent weekly shows! It really takes a great deal of real energy to pump out weekly shows and keep them fun & Interesting. Might be off scientific topic but Sabine is really cute!
How is travel time calculated? I doubt you can save a lot of time from a short haul flight compared to taking a train if you include transport time to and from airports and check-in time.
Thank you! I listened to one of the authors of the black hole / Dark energy paper on Fraiser Cain's channel and found it fascinating . Was I convinced of a ground breaking discovery? No, but interesting ideas presented.
Fraser is "interesting". One the one hand, he presents professionally and has impressively deep knowledge of his topic. On the other hand, he seems easily taken in by new ideas.
The wonderful YT algorithm offered that video to me but I thought "not likely" and gave it a miss.
Each to their own.
@@AndrewBlucher When talking about a 100+ year old problem that no one has even an inkling of an idea of how to solve, discarding new ideas will never get you an answer.
@@BenjaminCronce Which 100+ year old problem is that?
Dark matter can be traced 1933, dark energy to 1998.
People come up with new ideas all the time. The questions they need to answer are what is the mechanism, is it testable, does it make predictions?
Take string theory. Has it actually produced any results? Apart from beautiful math and lots of papers?
9:31 planes can be delayed too. In most countries they are even more often delayed than trains, especially if you count longer delays (delays under 1 hour are not that relevant because in this case passengers usually have enough margins to still get their connecting flight).
Sabine, when you say "micrograms per liter" and the visual shows "mg/L" is that a typo, or does Germany use a different abbreviation for micro than the US does? I'm accustomed to seeing microgram being abbreviated "ug" (using mu if available on the keyboard, or lowercase U if it isn't). In the US, mg is "milligram" and mcg is commonly used by pharmacists for "microgram". Thanks if you can clear this up.
It's a typo, Germany uses µg as well.
Thank you for the µ. :-)
Oh, I thought they were only claiming a correlation. Thanks for the update.
I love the idea of making fuel by extracting carbon dioxide from the air, in fact I'm thinking of patenting my own method - I call it 'Trees'.
I'm a retired forester, and I think we patented that name a long time ago, but thanks for the lol!
Totally with you on synthetic hydrocarbons for hard-to-decarbonise uses!! Have been saying this for years but I don’t have quite the same platform. 🙂 Long-haul air travel being a perfect example!
Unburning ashes into fuel is Socialism removing a randomly brutal god by substituting determined committees.
I would not say that it is underexplored, though. The problem is efficiency, where the direct use of electricity and even green hydrogen, in some cases even the use of natural gas, are still with a much lower CO2 footprint. I agree. This can only be a solution for very hard-to-decarbonize areas.
I would go as far as to say that short haul air travel will be electrified in the next decade.
That copper catalyst could be really useful if the process can be made efficient enough.
Sure. I wonder how much energy it will take and how much seawater must be processed to take 20 billion tons of CO2 out of the oceans every year, and then turn it into dry ice, and then sequester that ice underground somewhere forever.
@@LcdDrmr
Why bother? We have other uses for it.
@@waynesworldofsci-tech Of course, I was addressing it in the context of the video, as a way of reducing CO2 in the atmosphere.
Insightful. Thank you.
Thank you Sabine, this was excellent as always!
what happens with the copper? does it oxidize in the process
are we using up a rare metal that we have shortages of to produce fuel for a little longer
or is the copper unharmed and possible to be used indefinitely
this kinda sounds like just pushing the problem forward, pushing it forward with something already in short supply causing two shortages instead of one
Matter never gets used up. It might require energy to refine back to a useful state, but it's never used up.
@@WeighedWilson we have no perfect energy transfer
we use energy to make a fuel to produce less energy that we then can dump in energy to make the resource back
the transition would be a loss
we dont have excess to dump into a loss
no, rust is gone in practical terms
The paper regarding the evidence for cosmological coupling of black holes is super exciting. This could easily be the most important discovery in cosmology this century. I’m looking forward to the many many papers that will be published over the next few years as everyone digs deeper into this.
I'm super excited to defeat the local curvature of spacetime's efforts to mess with my ankles by lying on my sofa. The methode champagne's a great excitement magnifier too.
Best channel in the entire universe. I've visited a lot of planets, but this channel ist by far the best one. Many thanks to Sabine
5:38 my god that was brutal and the punchline made it even better💀
At 17;30 Id like to see selected ocean grasses.
The way water moves is key.
: )
This week I have learned about soft photons and the black hole - dark energy relationship
@@theta-rex prove it
@@theta-rex I'm not aware of whether dark energy and dark matter fall outside the scientific method, but those claims need references
@@theta-rex 🤔 You can use maths to prove that for example √-1 is outside the real numbers...
to me it sounds quite plausible that black holes influence the curvature of space in a way that is consistent with the cosmological constant. i aggree though that the name dark energy is a bit misleading
7:10 I don't get why solar systems like ours are the least common, when it looks from the graph like they are the second most observed. Are the models trusted more than the observations?
yes, that baffled me too.
Same...
18:25, I believe the written version is correct as CO2 is about 1mg (milligram) in the air, not microgram as said by Sabine.
Could you discuss thorium reactors. Some people think that they will solve all our energy problems. I have not heard a careful and not biased discussion.
I talked about thorium reactors here ua-cam.com/video/0kahih8RT1k/v-deo.html and at the moment I don't have much more to say than that.
@@SabineHossenfelder fantastic, I will share these with my daughters in the hope they follow you into physics. Or at least, nuclear engineering.
@@SabineHossenfelder Thanks for your response. I am interested in more details about thorium reactors. They say that they cannot be used to make a bomb, why? They say that can't be used to make a dirty bomb, why? That thorium reactors are safer in emergency situations, why? An end of life thorium reactor is easier to deal with, why? The isotopes produced in thorium reactors have shorter half-lives, is this true? I know that thorium was not of military use in the 1940's so research and development was not funded. Is this the only reason that we don't use thorium today? It seems that there are only thorium enthusiasts and everyone else who ignore them. Thus, no detailed discussion.
Thanks Sabine excellent discussion ☕☕
Damn I wish to see something under pressure in this episode
Without Sabine, life sucks.
Great video! ^^ ❤
An apparent increase in mass of very old objects is something I would expect from GR. Specifically, if you think of gravity in terms of time dilation instead of potential, the manifold's curvature into the time dimension should increase over time regardless of whether the object is accreting new mass just because time ticks more slowly the deeper you go in the gravity well. As you evolve the manifold (defined as all points with proper time equidistant from the origin) forward in time, the parts deep in the well will continually lag behind. That it's connected specifically to the general rate of growth of the universe should be expected since gravitational collapse can be seen as a consequence of expansion or vice versa in a closed thermodynamic expansion model.
What mechanism would increase the mass of a black hole? Time dilation has nothing to do with it.
@@tonywells6990 A more intuitive way of thinking about this is that it has more to do with the observations which are used to infer indirectly the mass of the black hole based on the Doppler shift period of material accreting onto and or orbiting around it.
If the rate of time passing is slowed down by local time dilation then you will observe a broadened spectrum suggesting that the distance of the accretion disk and thus consequently the mass of the black hole is larger than it would otherwise be. Hence the black hole appears to be more massive (and older if we assume all the observed redshift is purely due to distance rather than partly due to curvature of spacetime) to a distant observer than would otherwise be expected.
@@Dragrath1 And no evidence of any of that.
I’ve been waiting for her video on this! I knew it would be coming soon
The black hole thing has always interested me. I mean, if space is expanding outside of black holes, wouldn't it be expanding inside the black holes as well?
No, because space only expands on scales large enough that gravity doesn't counteract dark energy. Black hole is not a large enough scale.
As Guy correctly says, whether or not an object expands with the universe depends on how strongly it is held together by gravity. Black holes are held together too strongly, they don't expand. Neither do, for that matter, stars or planets or atoms.
@@SabineHossenfelder Where does my belly fit into the scheme of things?
@@alankott3129 darc beer energy?
By definition, black holes don't grow. They are singularities. The event horizon of a black hole does grow as it's gravity increases but the black hole itself is infinitely small no matter how much stuff it eats.
Thank you very much for your succint recap of the news! Can you please provide links to the research? I am particularly interested in '3D printing wiht sound' paper.
Thanks Sabine, 1m subs soon? :)
Would love to see the short haul flights analysis for France
I like how when they just don’t know where or what something is they just label it as “dark” and move on.
😂
I don't know, therefore dark "X".
🙃
"Move on"? In what way is conducting extensive research "moving on"?
Try not speaking on things that you clearly know nothing about..
Uneducated statement
@@pooperhead1023 he is not lying, my maths lecturer worked on dark energy, he said the same thing. Not trying to discredit scientists though.
I like passively watching. Great videos, I hadn't discovered this channel yet.
I have seen research I never knew about here.
Your friends are richer than you today because they have a key that you don't have and that key is good investment, build your income now and be part of the big guns in today's economy.
If you don't find a way to multiply your money, one day you'll wake up and realize that the money you thought you had is gone. Investment is key.
l agree with you mate. Investing is the
key to maintaining your financial
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@@economistasincero2780 My investment manager is Mrs Jennifer Allen , she is an expert when it comes to investing that produces a good percentage profit rate.
@@drmarkalexander4142 how do i get started
@@economistasincero2780 she's on what" sap👇
Watching Sabine’s weekly commentaries I am assured that cosmology still holds many more contradictions and unresolved questions than our wishfully advanced knowledge would hope.
Okay, longer "travel times" when you take a train instead of a short-haul flight, but you also don't waste a lot of time travelling to the city outskirts to get to the airport, get through security, get on your plane, get off the plane, claim your luggage, get out of the airport, get back into the city you want to go to. If you take a train, you probably go to the city centre, get on the train, get off the train, and you are directly in the city.
That of course doesn't mean that rail services can be vastly improved in Germany, but a lot of people seem to ignore all of this extra time before and after the actual travelling part of the trip.
I was eagerly waititng for your video on this topic after two papers came out :D
???? Why would you multiply all the percentages? 33% are short haul flights (even if 1500km is arbitrary). It is irrelevant if they are domestic or international. It is also irrelevant if they are also carrying only passengers, or only carrying freight or a combination. The goal is to encourage a more carbon neutral method of transport. Not all trains are run on diesel, or by coal-fired electricity as in Germany....
Further, if you look at the original source you can read that the 2.4% of global CO2 emissions in 2018 from fossil fuel use is a 32% increase over the previous five years. Further, this emissions growth rate is 70% higher than assumed under current ICAO projections. As covid bans are now lifted, we can expect more travel.
The first few seconds sound like a 90s Jan Tenner Audio play and I love it 😅