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1. ## How does space get inside of an inflating balloon?

According to Dr. Nima Arkani Ahmed it is. Scroll to minute 37.
2. ## How does space get inside of an inflating balloon?

Raisin Bread is not a good analogy. It suggests that space is expanding. Space is being created.
3. ## How does space get inside of an inflating balloon?

The volume of space is changing as a function of time. Space in not expanding, it is being created everywhere at once.
4. ## How does space get inside of an inflating balloon?

Space is being created everywhere at once as a function of time. There is a doubling factor. That is why things further away move away faster. If you make a grid of space with say a galaxy "A" in one grid and another galaxy "B" in the grid next to it and another galaxy "C" in the grid next to that, after one doubling the galaxy "A" would see galaxy "B" twice as far away and galaxy "C" 4 time as far.
5. ## Proton/Neutron - Fermion confusion.

You can't take the two ups and a down for a proton or the two downs and an up for a neutron too literally. There is a soup of things in the proton and neutron. Lots of gluons, lots of up, down, top, bottom, charmed and strange quarks all interacting with each other. At any one time there is a net positive charge in the proton because on average there are two more 2/3 positively charged up quarks and one more 1/3 negatively charged down quark in the soup giving a net one positive charge. The neutron having two down quarks at negative 1/3 and one up with positive 2/3 positive charge cancel out to make the neutron neutral in charge.
6. ## Space-Time Boundary Inquiry

If space is being created as is the theory, then nothing is required to move into. I recently watch a lecture where the expansion was explained this way. If you are at a point in space, and space is doubling in time. If you make a grid with our galaxy at the center of one grid and another galaxy is at the center of the grid next to yours and another galaxy is at the center of the grid next to that, every time there is a doubling of space, then every someone, including you, would see the others moving away from each other faster and faster the further away they were. The one that was in the next grid would be 2 grids away and the one that was 2 grids away would be 4 grids away and so on.
7. ## Lorentz Transformations (split from why nothing >c)

Not sure if this is relevant, but if two electrons are speeding toward each other, they are being repulsed by the EMF. Once they get to 10^-31 cm apart gravity takes over and becomes the dominant force.
8. ## Big Bang theory

Matter and space are separate things, You have clumps of matter and you have space between them. It is the space between the matter that is expanding. If you extrapolate this expansion backward in time, you come to point where there is very little if any space between the clumps.
9. ## Is time a property of space or the fields within it?

I just watched a lecture by Nima Arkani Hamed. He says spacetime is doomed and it needs to be replaced. He talks about how it breaks down at small distances(10^-33cm) and times10^-43 s). At those small distances(Black Holes, Big Bang) the Uncertainty Principle makes the Energy so large in a tiny region of space that time ceases to be something meaningful.
10. ## Why nothing can go faster than speed of light.

If someone fired a killing light beam at some one else, and you went faster than the speed of light, you would see the person die before the light beam hit them. So isn't that reason enough?
11. ## Universal 'Now' at Time-Zero

Has anyone seen this you tube video by Nima Arkani Hamed? He talks about what is being discussed. It is quite interesting and may have some answers for you.
12. ## Lottery Calculating Trouble

Is it not possible for the gaming people to rig the system? Like the OP said. Looking at the numbers that are picked the most and set up the computer generated picks to pick them less often to increase profit? Could a casino see what are the most popular number bet on in say roulette and tinker with the wheel to make them less likely to come up. Maybe by doing something with the wheel's bearings that make some numbers/colour less like to be stopped on? Is there any agency doing oversight on the gaming commissions practices? I know there is a dial in the slot machines that can adjust how much is paid out, but I am pretty sure that is advertised in each casino what the pay out is. Like 4% or 4.2% or whatever. Is anyone/agency checking?
13. ## Time Travel Simulation

If everything in our Universe has a position at any instant in time. And the passing of time is just how those positions relative to one another change from one instance to another, then each instant in time would possess a unique configuration. This would mean that every point in time would also have an unique initial condition that every subsequent point in time would be dependent on. Chaos theory say that if you change the initial conditions, then time will unfold differently. If one could send anything from one point in time to another, the initial conditions would be different from both points in time. Time would unfold differently for both timelines. Even if Ron Mallett sends neutrons back in time in a spin up and spin down configuration as a binary code to send information like say the lottery numbers, it would change the initial condition from the point in which they arrived and the numbers would be different in the changed timeline. I think.
14. ## Effect of collisions while travelling at relativistic speeds?

http://www.biblehelp.org/ufo4.htm
15. ## what exists at the edge of our universe?

Another interesting area of research is the existence of "chameleon fields”. This was first hypothesized in 2004 by University of Pennsylvania physicist Justin Khoury. Ten years later English physicist Clare Burrage proposed a methodology for testing their existence in a laboratory using atoms. Paul Hamilton of UCLA has conducted experiments to test for these "chameleon fields”, where Dark Energy may live. No smoking gun yet, but they have put restraints/doubts on some of the proposed theories. Also experiments have provided a better understanding of how strongly "chameleon fields" can interact with normal matter. Baby steps.
16. ## what exists at the edge of our universe?

Right. The Bullet Cluster is evidence for Dark Matter. But I think he believes that all of the Dark Sector(Dark Matter and Dark Energy) is probably true.
17. ## what exists at the edge of our universe?

Sean Carroll does his best to wave the banner for Dark Energy. In this lecture he gives some compelling observational evidence for DE based on the Bullet Cluster. But, Milgrom's MOND(Modified Newtonian Dynamics) theory works on a smaller scale. Jacob Bekenstein TeVeS(Tensor-Vector-Scalar) is a relativistic generalization of MOND. You be the Judge!! Some links of interest. http://www.astro.umd.edu/~ssm/mond/ https://en.wikipedia.org/wiki/Tensor%E2%80%93vector%E2%80%93scalar_gravity
18. ## what exists at the edge of our universe?

The TV series Through the Wormhole has an episode on this question.
19. ## A logical approach to gravity at the quantum level

I thought you guys were pretty lenient. Logic and nature are not the best of friends. You can use logic to dream up a theory, but you need observation to agree with it, all observation, to make it real. And you need some mathematical model that accurately predicts something that can be tested and also agrees with what is already observed. The questions posed to the idea presented are not done to make it look stupid. There are to help it make sense and point out areas of concern that need more rigor.
20. ## Universe in a Black Hole

Two things we observe. One is that all Matter is moving away at velocities that increase proportionally with distance. Two is that space itself is also undergoing an radial outward expansion. If our Universe is inside a BH, and all the matter inside is being accelerated toward the singularity, then the horizon of our observable Universe would be the point at which the light is redshifted out of our perception. Wouldn't it appear as if everything is moving away from everything else? We are, I think, reasonably assured that there is an expansion of space happening. We have added a new degree of freedom to explain it. Namely Dark Energy. We know that Dark Energy does not change as the Universe expands. It is entirely possible that it is completely constant in terms of an Energy Density(10^-8 ergs/cm^3). So is the expansion of the Universe a result of something in our Universe like Dark Energy? Or is this observed expansion due to space being drawn/stretched by the singularity of the BH our Universe has happened be swallowed by?
21. ## Universe in a Black Hole

A BH radiates energy or equivalently mass. The evaporation time of a black hole is proportional to the cube of its mass. So a BH that is swallowing universes could be taking in more mass than it radiates and getting larger or it could have reached an equilibrium of mass swallowed to mass radiated. Even if it wasn't taking in any mass it would still not shrink much over billions of years. An observer in a swallowed universe, I am speculating, would see all matter moving away faster and faster the further is was from the observer as the matter moved toward the singularity. Spacetime would also be stretched towards the singularity. Since all paths lead to the singularity it would appear to an observer in the swallowed universe as if spacetime was expanding in all directions. I am still working on the details, which may not happen in my lifetime.
22. ## Universe in a Black Hole

I didn't want to hijack the Black Hole thread I was following, but something occurred to me. If we scale up the BH to an enormous size, our entire Universe could theoretically have crossed the EH and following a path to the singularity. Could that explain the expansion of space(dark energy) we observe in our Universe? And why Galaxies are racing away as the get further from our observation point and closer to the singularity? I have no idea even where to start on the math. I guess first would be to see how massive the BH would need to be? Then how space would need to curved so that light we see coming from he edge of our observable Universe would appear to be approaching from all directions. Is this a worthy project? Or an exercise in futility?
23. ## black hole, singularity...

(Correct. To put it in math form, let's say the spaghettification occurs for an acceleration of where is a value greater than 100 and . On the other hand, the EH is at So, spaghettification happens at a distance from the singularity: i.e. It is possible to have if : ) The above condition can be fulfilled for supermassive BHs) Thank You for the math. It would have taken me years. All paths lead to the singularity once the EH is passed. Either directly or asymptotically along the EH? That is what it looks like from Professor's Susskind's drawing. There would not be any cancelling of forces. Wasn't that the original question?
24. ## black hole, singularity...

So as is it says in problem #5, if the BH is large enough, it is possible for Bob to cross the EH without realizing it? At least for a while.
25. ## black hole, singularity...

How massive would the BH have to be to make the tidal force at the EH not be noticed by Bob? Say M = 10^70. Would that make the EH radius about 10^ 47? Would the tidal force at that distance from the singularity be small enough to be unnoticed by Bob? Sorry my math is not great, but do I have the orders of magnitude right?
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