Brian Cox and Jeff Forshaw discuss The Quantum Universe
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- Опубліковано 7 вер 2024
- EVERYTHING THAT CAN HAPPEN DOES HAPPEN
The first in a series, watch Brian Cox and Jeff Forshaw use quantum mechanics to discuss Why We Don't Fall Through the Floor.
Read more on The Quantum Universe: bit.ly/pmL4Q7
@TheCarnun That shows some good understanding and is true. Yes, absorption of light by electrons accounts for the reason why some objects are opaque, but there is more to it than that. For example glass and plastic may be transparent because they have they either have no crystal domains (regions) or they are smaller than the wavelength of light. You get some plastics that have crystal domains with similar size to the wavelength of light, and are called semicrystalline.
i bet the hardest part of these guys' careers was doing this interview and dumbing themselves down to each other
There are plenty of stars larger than 1.4 solar masses. These stars are 'active' and it's pressure produced in the cores of these stars by nuclear fusion that stops them from collapsing in on themselves. What's being said is that you can't have a star bigger than 1.4 solar masses if that star has stopped it's nuclear reactions, i.e. a white dwarf.
I love it that you calculated that number. :) Makes me happy...
the book is great has humor and gives you the way of thinking as well as the tools to work it all out
Yes, but generally speaking the larger a star is, the less dense it is compared to our sun and other smaller stars. Think about it like a ratio of volume, mass (weight - different but proportionally similar) and density. So it is analogous to the 'empty space' discussion of matter, you can imagine that there is essentially more empty space in larger stars between atoms and molecules by comparison to smaller ones.
I may just be ignorant... But doesn't light pass through glass because the whole of our visible spectrum doesn't carry enough energy to give the electrons a 'boost' up to a higher energy state? (Making the 'energy gap' of electrons in glass quite large, relatively, to other 'opaque' materials.) Which would explain why some materials are translucent and coloured, when only some visible wavelengths of light make it through while others are absorbed in raising the electons to a higer-energy state..
@sebpines
Already reading it. It is truly amazing. Brian manages to explain the concepts so simply yet with such clarity.
And there 's my fat as* over here, thinking about eating the Croissants 🥐😂
but your didn't explain why!
Yes but is it really 1.4 solar masses . what if the thing is rotating at speed.can we increase the mass . and why do blobs of stuff not fly off. is this solar flares . is the sun rotating at speed?.
Paul.
Brian is always smiling never seen him not smiling
@virumoz It`s his lovely Manchester accent.!!
Let me tell you stewjw Jeff most certainly did not have free education, he got were he has on hard graft, a love for the subject and help from his parents in paying for his university education.
Just got the book, Its awesome ;-)
Thanks :)
Careful here!!Between nucleus and electrons there is NOT empty space. There are exchanges of other particles, therefore frequency and energy everywhere. So; giving the strong and week forces that are permeating the atom, and other generated by interactions , indeed, we do not go through the floor! Beside, the dimensions of subatomic particles, and therefore space between them, are mathematical postulations, almost impossible to define properly in words....
This isn't recorded loudly enough to hear, and the British accent makes it hard to understand what can be heard.
I'm only 15, by the way... So I hope that justifies my misunderstanding :P
Just think both these guys had a free education unlike Physics students today. I also wanted to study particle physics at QMC in the eighties but they wouldn't let me in due to my poor maths. To be honest although I was fascinated by the subject I didn't think it had much of a future as a career in a Thatcherite austerity Britain. How wrong I was.