The Broken Cosmic Distance Ladder
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- Опубліковано 3 лют 2022
- Measuring distances to astronomical objects outside our Galaxy is a surprisingly hard challenge: it wasn't until 1923 that Edwin Hubble obtained proof that Andromeda is indeed a galaxy in its own right. Today, astronomers extend distance measurements in the cosmos to the edge of the visible Universe, building up a 'cosmic distance ladder' made of several rungs.
This talk will explore a major conundrum of contemporary astronomy: as observations have become more precise, the distance ladder appears today to be broken.
A lecture by Roberto Trotta
The transcript and downloadable versions of the lecture are available from the Gresham College website:
www.gresham.ac.uk/lectures-an...
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I like how he mentions the term "computers" in one of it's oldest consistently used ways.
Groups of women entrusted with observing astronomical photographic plates, and computing the figures needed to ascertain stellar distances and types, among other astronomical phenomena.
The term "computer" in this specific context is exactly what people like von Neumann and Turing were thinking about when they began calling computers "computers".
They knew where the original credit and responsibility lay. They started using the term, instead of "Giant Adding Machine" or "Difference Engine" or even "Calculator".
Computer.
The term "computer" dates to the early 1600s, when it referred to drudges who did arithmetical calculations.
@@kevinbyrne4538 Someone(s) been keeping that term alive a lot longer than the story I heard. Words. What a concept!!! :-)
The anomalies are piling up meaning things are ripe for transformation. Looking forward to real drama in astronomy, cosmology and fundamental physics in the years ahead.
electric universe and plasma physics.
Halton arp showed galxies with different redshift which were connected via plasma bridge. Quasars are ejected out of galaxies and have different red shift from their mother galaxy. Redshift is not a measure of distance.
@@Sulucnumoh420 just because lambda-cdm could turn out to be wrong that doesn't mean that EU and plasma stuff will turn out to be correct. better to keep your options open
If you read some peer reviewed papers on this topic. You will see that the difference in expansion is calculated in, it’s also calculated in our own current place and velocity in the universe, our sun’s spiral motion, and that the Milky Way is turning and being dragged towards a place in the Lania cluster and how this effects our calculations under the theories of Einstein/ gravity and time. I think we need to remember that these calculations are not made by 1-5 people but thousands, and that scientists are tripple checking results before they publish.
I was helping a team calculating some “small datasets”, and top of the line cloud services (many servers in AWS and Azure) as of 2021 spent over 1 week for each run trying to statistically find the most probable area to look, because we can’t look everywhere yet, because we do not have the computing power. We spent 8 weeks just trying a few hundred models in order just to find a small place in the sky.
There are already well established methods of making sure that there are not errors due to equipment, human error, logical errors, flukes etc.( but they still exists).
So there is, as the prof. is saying, most probably something we do not understand yet.
if you came for the title and not a 'black hole style' potted history lesson then skip to 55:00
distance ladder is broken there are three things it could be - they get one minute each at the very end.
Thank you. That was a very entertaining and cogent lecture about the distance ladder. I did subscribe and I will pay attention to your future lectures.
what a brilliant exposition. a natural communicator.
This is one of the best lectures I've ever enjoyed. Everything is presented clearly and vividly. Professor Trotta is a star!
yeah, he could get quicker to the point though instead of reciting poem
I'd like to point out we're not in _Space,_ we're in a gravity well of Earth which is in our Sun's gravity well, which is in our Milky Way's gravity well. This is non-homogenous with the majority of Space itself, and thus slows our rate of time relative to it, as it would do with anyplace else, with its own gravity well. Time slows the deeper in the well one goes. This difference may be what we have just been looking at.
pretty sure they take that into account as its a very well known effect . Its a shame we do not know more about gravity atm
Wonderful talk, thank you.
Interesting both from science and history!
History beating US debt baffles 'science' of Economics report says in New Witchdoctor Magazine - Bones of ancient Mathematicians are cast and how they fall predicts the future
Brilliant Teacher
An analog mechanical clock is a specific emulation of the relevant aspects of real-time daily cycles to organised integration of commerce.
If you know the relative-timing ratio-rates of the hands on the clock, it's possible to judge distances in the wave length/frequency relationship, and a somewhat similar technique is used to describe Celestial Distances. Only AM-FM Timing-spacing coordination exists in relevant fact, and the actual distances in space are incalculable because eternity is infinite "emptiness", the pure-math function of continuous multiplication and division, creates the Eternity-now Interval Conception Superposition-point Singularity Perspective, in/of this e-Pi-i sync-duration Principle.
Ie just as we see the continuing accelerating expansion of the Universe, we have determined that the world around us is the reciprocal condensation of functional Superspin, inside-outside logarithmic condensation-coordination at Singularity, this Centre of Time Duration Timing Conception, that is what, how and why we can understand the real probability in potential possibilities of uninterrupted continuous containment.., here-now-forever.
An excellent review of the history of astronomy, thank you. Concerning the discrepancy in Ho, Wendy Freedman gave an interesting lecture in the Golden Webinars series recently. Her analysis of the possible uncertainties in the late universe data suggested +/-5%. I think the biggest lay in the effect of metalicity of the supernovae.
As always, we need more and better data.
Thank you for this and the other insights you give us into our marvellous universe.
What an amazingly bright lecture. Thank you Professor Trotta!
Another brilliant lecture by Professor Trotta.
Will the Webb telescope help in refining some results, or are we waiting for gravitational waves detectors?
very cool
Einstein was so bright that recognized that only a supreme being could create the universe because it is perfect.
that was profound!
I agree. A superb, informative, interesting lecture!
Since we have no idea how the fine structure constant is produced, it could easily be it is changing.
We can observe the isotopes created by a natural nuclear reactor in Gabon a long, long time ago. The results are inconsistent with a changing fine structure constant.
What I would like to know is exactly at what distance modern astronomy fails as to distance. I would assume it stands between 500 million light years and 1000 million light years. As at this distance most of the failures of modern astronomy disappear, like dark energy and other failures such as dark matter which only shows up in galactic rotation. This would indicate a failure at hundreds of thousands of light years, not millions. So the scale runs off the ruler at these distances and I suspect it has to do with quantum reality, not something like dark matter.
Wow, thanks! Solves everything.
At 16:00, I must be missing something. The sun is far too close to treat it as a non-moving distant (infinite) star. Also, the radius of the sun and its apparent radius from here would tell us the distance without observing Venus, so the size of the sun was not known. So, how can you interpret the observed parallax of Venus to scale 1 AU?
I saw the transit of Venus live using welders' glass - I measure Lunar distances in $100 US debt bills soon it will be $1000 bills
It is not necessary that the sun is not moving - they make the observations on different locations at THE SAME time. As can be seen in the graphics he shows: One person/team in Canada and the other in Tahiti.
Probably they make multiple of measurements and precisly note WHEN they made it so they can compare those that were taken at the same time.
Of course - time measuring wasnt by far so precise as today. But... if you have a lot of time to prepare they were able to come really close to what was needed to reduce the potential errors a lot.
@@BoothTheGrey WHEN the measurements are made is irrelevant to the geometry. They still have only ONE side of an (or two) isosceles triangle(s). A thought has occurred to me since my post, but I don't have their data to check my calculations.
@@byronwatkins2565 The time stamp is usually relevant when you have moving objects relative to another. The geometry then depends on when you measure in moving systems.
Measuring parallax has nothing to do with "non-moving", but is also possible when all objects are moving. But then you have to check out what the movement means to your geometry and which comparisons make sense.
When you have four dimensions (three space dimensions and the one time dimension) it helps not to think only two dimensional.
But... in this certain case the moment is already chosen by the situation itself, cause when I understood right after reading a bit more about it, they compare the two transits of venus from different locations. Therefor... you can just forget about the time dimension cause the transit is only happening at one very special time point.
You do measure it at the same time from two different locations and check out the differences.
So in THIS measurement... the movement of the sun (and also the earth) is not important to have a first idea of the distance relative to each other. Of course it would get important the more and more precise you wanna measure. But it was the first approach. They knew that the measurment contained a lot failure potential but was a huge step foward.
@@byronwatkins2565 they had two angles as well. Angle-Side-Angle gives the whole triangle.
Why can not the discrepancy H0 values be due to the fact that the Hubble-Lematrie constant is in fact not constant. Especially because the rate of acceleration of the expansion of the universe is thought to be increasing? I can find no discussion about why such an idea is not even being considered?
It's indicative of the problem with science currently....no one is questioning the axioms.
Ok, I really don't get how we can detect space expansion. We ourselves are the space, we are not somehow outside it right. So if the space expands, literally everything does ,including size of atoms, electrons, quarks, everything. So how can any redshifts be an indicator of space expansion? It's certainly an indicator of a receding object but how of a space itself?
We do measure redshift using spectroscopy comparing spectrum to the reference spectrum of the sun but this all is expanding right? The space doesn't expand into anything(i.e. it doesn't increase in size measured using the space means itself as we do because surely we would need to notice that earth,sun,etc are getting slowly infinitesimally bigger) it just expands everywhere right. So how come it should somewhat expand faster the further away from us it is? It suggests that a sphere around us expands which isn't true since in an expanding space a sphere around any single point in space needs to expand including the very point itself. If this is so then this can never result in any detectable distance delta from any vantage point and hence no detectable speed of expansion, can it?
Is that "speed of expansion" we measure some sort of accumulated effect over vast distance? Meaning here on earth we cannot really detect it but since every quantum of space expands the effect accumulates with distance? But that also makes no sense since if I have an image and I'm expanding it (zooming it in) I'm slowly getting pixelation and can measure the zoom speed, but that's only because I'm outside of the pic, inside of it nobody notices anything right? How could they?
the things in it dont expand, just the space does..
@@andyf4292 how come? Ultimately there's no "things"only energy vibrations besides everything is a space ultimately.
Moreover if the stuff remains the same then the space expansion would be equivalent to inside of the inflatable balloon in which case what makes the far objects to speed away from us? Some sort of "space drag" or we blame dark energy? But then how come that galaxies are not torn apart by that expansion? And why the only repulsive force when calculating galaxy rotation/mass is the centrifugal force?
@@jimjimmy2179 When people say the universe is expanding, they're not talking about things at our scale. Objects within space, including quarks, atoms, and us, are not changing size. Galaxies are moving apart from each other because the AMOUNT of space is increasing, which means there's more space in between the galaxies that exist. Galaxies stay together because of gravity, but all galaxies that are too far away to be gravitationally bound to each other are moving apart. The Andromeda galaxy is moving towards us, for example, because Andromeda and the Milky Way have strong enough gravity to pull each other in. Almost every other galaxy is moving away from us at a speed that depends on its distance. Someone in those galaxies looking at us would see the same thing - all other galaxies moving away from them.
@@noshiko5398 yes, I also mentioned the option of "amount of space increasing" in my comment which seems to violate conservation law, plus my very body is 99% of "space" so it really should be getting bigger.:) Still doesn't doesn't explain the mechanism behind light red shift providing the light speed is the same regardless on any inertial frame so how can ever anyone observe a red shift from any receding light source? The sound Doppler effect mechanics on the other hand is pretty straight forward.
@@jimjimmy2179 Your body is held together by atomic bonds, which are much stronger than gravity. It's not getting bigger. What people mean is that the space between galaxies, galaxy clusters, etc. that are NOT held together by gravity is increasing.
About your redshift comment: two things. First, you're misunderstanding what redshift is. Redshift is a change in the frequency (which in visible light corresponds to the color, hence the name "redshift") of photons, not the speed. All light travels at the same speed regardless of its frequency.
Second, the more important problem here is that you're looking for explanations for mechanisms of the universe that make intuitive sense to you, but just because something makes no intuitive sense to humans doesn't mean it's not real. The explanations given in popular-science videos are only analogies, and you shouldn't take them as anything other than that. We understand physics through mathematical models. The math predicts that objects emitting photons and moving will have their photons shifted in the electromagnetic spectrum based on that motion. When we observe objects in the universe, we see light that follows those patterns. That's how we know redshift is real, if you're trying to justify it solely through analogies then it's not going to make sense.
The broken cosmic distance ladder is shown in dark energy and less so dark matter which is probably just non-ionized neutral hydrogen with almost no unknown particles, forces, or unknown galactic effects other than distance attributes of quantum uncertainty regarding distance.
Confirmed uncertainty about an election result was interesting when the cosmos gave a Woman 4096 more votes in a voting machine due to high energy particles - After 2008 financial crimes US executed 6 Women voters
Would someone please plain where Halton Arp went wrong please...
tell us why he is right if you're so certain JJ
“The Final Theory: Rethinking Our Scientific Legacy “, Mark McCutcheon.
At 22:50: Wearing suit and tie in Haitian summer? No wonder the guy did not make it home. Mad dogs and Englishmen go out in the midday sun.
3:45 parallax
If the universe is collapsing faster than the speed of light we will never see it coming
The Broken Cosmic Distance Ladder 1008am 5.2.22 it'd be something of a bummer to detail the expansion of our galaxy and just as we had reached the cessation of it's mapping that the findings were lost due to the universe having collapsed in upon itself. diligent reapers of the planets would probably chuckle at the paradox. pretty much hitchhiker's guide to the galaxy kindda musings but.. yeah... heavy going if you had to formulate the maths!!!
better kiss your pyles goodbye
@@Mrch33ky The Broken Cosmic Distance Ladder 6.2.22 035am other than a not so amusing rejoinder to the whole concept as you have seen fit to scrawl... and i am gathering by your high falutin' tone that you are far more learned than myself... Why do you think einstein has been over-hauled by alleged lesser known thinkers and why is the cosmic ladder not all that it should be? how has such a glitch in mathematics been allowed to remain? why are paradoxes such as this allowed to stand the test of time within the general theory of relativity when they do not conform to the seemingly overhauled einstinian theory? why has so much time and effort been put into promoting a theory which will be shown to be deeply flawed, should folk be allowed to put answers to this problem? and do you think some lesser minded man........ or woman (mustn't be sexist in such matters) will ever be allowed to promote an alt theory which takes into consideration the broken cosmic ladder wherein the maths match up and for one moment in time and space it all comes to a halt, stands stock still, as said maths are allowed to marry up into one large cosmic jest? while such as you grapple with the maths of the universe whilst making simple minded jokes... i wonder when the big man or woman with the maths is gonna come forward and be allowed to pit his wits against not but howls of laughter and shrieks of derision from the assembled mighty wits of these scholarly domains.....?
@@leszekkarpinski2796
Not even relevant
So to approximate, it's Ho = 70 (+/-3) km/s/Mpc near enough. (BTW You don't actually believe in Gravitational waves, do you?) - Boltzman would say in despair ''Not even wrong'', I suspect.
I betting on variable speed of light due over time. I know it isn't popular but it would explain a lot of things. Just a hunch. :)
How confident are you on a scale of 0-100? What is your confidence level based on?
yes, cosmic dust, plasma and intense magnetic fields could interfere with the propagation of light and shift it to the red
@@aaaaaa-qn8ol what is the liklihood that you are an attack chatbot...?
The universe expansion is at twice the speed of light...so you are right we are locally in the slow zone. So you are right and this local space-time is now. This should answer your question. As for local light speed and variable light speed over time in a local context...no and which means that the speed of light depends on quality of geodesics of our universe. This "grid" made of space time does not need to be equal everywhere, could pulsate or degenerate. That might give variable speeds over time. Caveat: studying geodesic termination and singularities for a long time...nuts, bolts, rivets and the boilerplate.
@@808bigisland I have heard there is some evidence that the expansion is not only variable over distance, but also discreetly (quantized?) variable or seemingly having what seem to be discreet borders between expansion speeds.
When I look at the moon, I see the Gerber baby. 🌕⛄️
Oh Dear, this lecture falls flat in its assessment of distance, once he begins to refer to the supposed Dopplar effect (red/blue shift) of Galaxies, which is itself assumed incorrectly to reveal an Expanding Universe. The Galaxies are NOT exhibiting a red (nearly all of them) or Blue (just a few of them) shift. Their colours are in reality a result of their contents, something I'm hoping the JWST will reveal to the shock horror of many of today's astronomers !! Red tinted galaxies will reveal this colour is the result of at least 75% of stars in them being Red or Red/brown dwarfs. While the few Blue tinted galaxies will reveal they have a rare abundance of large blue white stars, such as our neighbor the Andromeda Galaxy !
So correctly assessing Distance is itself still up in the air with regard to Galaxy + (plus) distances. I also want to point out that those Scientists "Still worshiping at the shrine of Albert Einstein", need to forget Albert & his first wife's 5 THEORIES from 1905, as after 117 years NONE of those THEORIES have yet been raised to the level of "SCIENTIFIC LAW" !!! As Nikola Tessla pointed out & indeed Professor Millar proved in the Laboratory, (both of them in 1935.) That the Theory of General Relativity is utter nonsense !!! So Scientists including the one seen above, are still deluding themselves.
Indeed until the daft Physicists & Astronomers wake up to the fact that another branch of science (Electrical Engineering) discovered and proved some decades ago, that Electricity working with Plasma, runs the whole Universe and absolutely EVERYTHING in it. Mainstream Physicists & Astronomers, who have NO qualifications in Electricity, are going to continue thrashing around in the dark, and getting it all totally wrong. As an Astro ELECTRICAL Physicist said at Bath University a couple of years ago. Quote "It seems none of our Astronomers are qualified to look through their own telescopes any more" Unquote. In reference to the proof the Universe is Electric !!!
THE UNIVERSE IS ELECTRIC THERE ARE NO ISLANDS IN SPACE.
It blows my mind that people that long ago could figure out the size of the moon and the earth. 99.9% of today's people don't know and all they have to do is look it up.
So, not really a broken ladder. Two ladders built using different sets of partial knowledge about the nature of the universe which fail to meet in the middle. Not at all a surprising outcome, really. The chances that two ladders, beginning 13.8 b light years apart, would meet exactly is quite small. The fact that they end within sight of one another is a remarkable scientific feat.
thanks from russia..... but there could be another world
43:50: every 3.26 light years, NOT 3.26 million light-years
I think you are incorrect: He says "It means for every MEGA parsec of distance, that is to say every 3.26 million light years of distance . . . " [emphasis added] The number following "that is to say" is simply defining "mega parsec." A mega parsec is a million parsecs and one parsec is 3.26 light years. An internet search for Hubble Constant returns
The latest estimate of the Hubble constant based on CMB observations by the Planck satellite is H0 = 67.4 +/- 0.5 km s(exp-1) Mpc(exp-1)
(Planck Collaboration VI 2020).
@@professorsogol5824 You are correct. I missed the "mega" part. Thank you.
2:19 min ... a meteor?
Old days they thought the stars where falling
WMP raw data was never released.
The one where the galaxy obscures everything else?
Lucid description from a valued researcher. The ending was abrupt, missing an introduction to the implications of this discrepancy.
Discrepancies are everywhere now Gresham showed the cosmic distance between London and the harried North - Spain Iceland Ireland jailed 10s of bankers while far off US executed 6 Women while *LUNAR* distances are many times smaller than $100 debt bills laid end upon end
“The Final Theory: Rethinking Our Scientific Legacy “, Mark McCutcheon. Hubble’s explanation was never correct. Pages 400-438.
I think "broken" is a poor word choice.
21st century Manchester to Leeds on the pathetic scale takes most of an SDP (Star Day or 1 Pathetic)
You are way too optimistic. Unless a very simple mistake in the methods of measurement is found, this problem will take decades to solve.
The Cephiad variables of Henrietta Leavitt 1921always like to here this story.
How can we even see the moon if we spinning at 1000mph ? How can we see the same stars if we traveling at thousands of miles and spinning 🙂
Motion only reveals itself during acceleration/deceleration and we are travelling at a constant speed. Also, the Earth is huge compared to the size of a person. So, although we are spinning at 1000mph, the Earth only moves a small amount of its total circumference ie. 1/24 during that hour. This is not enough to actually perceive Earths motion without long observation. ie. note the position of the Moon in the sky then,
an hour later, come back and check where the Moon is now, note the large distance moved by the Moon in that hour. This distance is mostly due to the turning of the Earth not the motion of the Moon. Yet, we do not physically feel or perceive that motion second by second.
@@jedg4746 Polaris proves we dont spin.
Um. With our eyes?
To talk of "spinning at 1000mph" makes as much sense as talking of "spinning at 30 miles to the gallon". Wrong units.
@@russellsharpe288 , Depends on the question in view. It's sensible to calculate the velocity of the surface of a spinning object. Ever jump of a fast merrygoround at the playground?