Cosmological Constant - Sixty Symbols

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1. The cosmological constant is in a Nother dimension
2. The Cosmological Constant is... 42
3. So Einstein makes his 'biggest mistake', by predicting Lambda, but then I hear you guys explain it still probably has some value. So what effect does it have to our universe, as compared to having the value of Lambda equal to 0? 
4. i don't understand... we are talking about the cosmological constant...so in what sense is it constant? is it constant throughout the universe's space or throughout the universe's time... or both?
5. At the end of the video he says the cosmological constant may exist but that it's value might be zero. If it's value is constantly zero then why would you consider it's existence at all?
    Wouldn't that mean it didn't exist?
6. Electromagnetic force is much much stronger, but its charge comes in two flavor. Over moderately long distance, the amount of positive and negative charges are roughly equal and their effect cancels each other. Gravity, though weak, is always accumulative. Over long distance, distance of planet, solar system, and galaxies, it becomes the only relevant force. The cosmological constant causes gravity to become repulsive at very long distance: on the order of the entire visible universe. 
7. I'm a complete layman but given that scientist now believe that normal energy/matter makes up only 5% of the universe, with dark matter accounting for around 26% (which causes galaxies to spin faster than they should), and dark energy 69% (causing inflation), why would gravity ultimately attract all matter (presumably causing "deflation"?) when dark matter hadn't been postulated (as far as I recall), and gravity being the weakest force? Is it a case of cosmology revealing new problems?
8. one of these guys sounds a bit like prof. brian cox, university of manchester?
9. Yeah, right. Except that LHS has the dimension of energy, while RHS has the dimension of mass. There's an equivalence between mass and energy, but they're not the same. You don't say 1 kg = 1 m either.
10. One of the most important things about a scientific theory is that it's falsifiable. No matter how beautiful the theory is or how long it has been standing. it can always been proved wrong. Like Feynman says: "If it disagrees with experiment, it's wrong!" Religion can't be proved, let alone that you can prove it wrong. Scientists may love their theories, they don't worship them.
11. If they do they're not real scientists. No scientific theory is eternal. There's always new research which may confirm the theory, but sometimes the results of this new research show the theory is wrong. Newton's theory of gravity was thought to be the ultimate one, confirmed by each new observation. But while still OK for everyday use, at a cosmological scale it doesn't work anymore. Newton couldn't explain Mercury's precession, while relativity explains it perfectly.
12. (cutting some corners) In Einstein's time the universe was assumed to be static. But gravity would ultimately attract all matter to each other, so that it would collapse onto itself. Which apparently didn't happen, so Einstein added the energy of the Cosmological Constant so that all matter would be pushed apart again to a state of equilibrium.
13. Let's say you devise a scientific theory, but when you do your calculations they end up as 6 = 5 So there must be something not right. What Einstein essentially did was change it to 6 = 5 + 1 just by adding the "+ 1" term. The "+ 1" is the cosmological constant. It fixed the equation, but there was absolutely no explanation for it.
14. Because it has to have the dimension of energy density
15. No, it's true. Ptolemy's model for the planets' orbits looked horrible, with epicycles upon epicycles. It was too much tinkering, it simply had to be wrong. And it is. Enter Kepler and now the orbits become nice and simple ellipses. Newton invented the maths to prove it. And for everyday use (ignoring general relativity, see Mercury's precession) it still holds.
16. They can't move at light speed; their mass would become infinite.
17. - "So what do you know?" - "I know calm down. Also my intelligent."
18. It's shaky because of his excitement
19. To answer your Planck length question: if you further blow up a balloon 5 cm in diameter, do centimeters become larger as well?
20. tye speed of light is, ready? CONSTANT!!! O.o the speed at which time passes is not determined by expansion of the universe, but in fact by your velocity.