# Search results

1. ### A Trapping the sun in a perfect insulator

So this is kind of a crazy hypothetical, but what would happen if you surrounded the sun in an invulnerable, perfectly insulating sphere that prevents anything from leaving. I imagine that as the sun heats up, the rate of fusion increases and the life time of the sun decreases. But that's about...
2. ### Need an explanation of sliding window for networking

So I have a school project that requires me to use a sliding window in order to transmit a file to a server, but I'm having trouble understanding how sliding window works. I don't really understand how rejects are done and how the program knows to send a new packet and then move onto the next...
3. ### B What would a supernova sound like?

I obviously realize that sound requires a medium to go through. However, suppose that there was a supernova and it was magically surrounded by an atmosphere that has the same composition and density as earth's atmosphere. Now, if you were far enough away so you didn't get wiped out, then what...
4. ### Theoretical meson beam weapon

There's this game called sword of the stars and one of the most interesting weapons is the meson beam. Essentially what happens is that mesons are generated and accelerated close to the speed of light so that they decay once they're inside an enemy ship, thus bypassing all defenses and creating...
5. ### How much could the Earth's rotation speed up?

I've noticed there are a lot of documentaries and youtube videos about what would happen if the Earth stopped spinning. However, I would like to know what would happen if the Earth kept speeding up, what would happen if it did, and the approximate maximum rotational velocity before the Earth...
6. ### Falling into a black hole and time dilation

So for an outside observer it appears someone falling into is slowing down and then gets redder and redder. But what about for the local observer? From the perspective of the person falling I would imagine that the universe would appear to speed up tremendously. Is it possible you could survive...
7. ### Why is NASA and curiosity still looking for water evidence?

So I always see in the news that the curiosity rover or some nasa study of previous data discovered evidence of water like its actually news. Wasn't it shown a decade ago that there is conclusive evidence that lots of water existed on mars? I don't get why they're still spending so much time...

Why is it that the smaller the black hole is, the more quickly it supposedly evaporates? It seems like a black hole should radiate energy proportional to the surface area of the event horizon. To me it seems like the evaporation should slow down the more the black hole shrinks because the energy...
9. ### The set consisting of random numbers with random lengths

Does the set of random integers with random lengths (the number of digits), which hypothetically would generate random numbers with random lengths for eternity, produce all possible integers? It seems to me that this is a natural conclusion but i've never seen a proof of this. A more incredible...
10. ### Absolute compression = true randomness?

So i've read from various places that maximal compression produces a truly random output. But suppose you were going to apply compression to a truly random series of numbers with something like LZW. Well wouldn't it be the case that since randomness often produces sequences which do not appear...
11. ### How does the Higgs field interact with black holes?

What happens to the higgs field around the event horizon of a black hole, or is this currently unknown? Does the higgs field permeate inside the event horizon? Can extreme gravity affect the field in some way by changing its properties?
12. ### What is the strongest magnetic field a human could survive?

So i was reading about how the magnetic fields of a neutron star are so strong that they would kill you at a certain range because it would affect the shape of atoms and mess with body chemistry. So what is the maximum number of teslas before a human would die, and how many teslas before you...
13. ### Evidence that time and space began at the instant of the big

What evidence is there that time and space began at the instant of the big bang rather than, on the other hand, that space and time existed before the big bang and that the universe simply popped into existence into preexisting space because of Murphy's law; or has this been dis-proven somehow...
14. ### Unorthodox "space" elevator idea

Would it be possible, instead of building a 22 thousand mile long space elevator, to make a large floating platform 15-20 miles high which would be supported by gigantic hydrogen balloons. You would then take off horizontally and travel into space from there since most of the energy costs are...
15. ### Differential equations, zero state response

Homework Statement Find the zero input and zero state response for the following system y''(t) + 3y'(t) + 2y(t) = 2 x'(t) - x(t-1) where x(t) = (2e^-t)*u(t) U(t) is the step function Homework Equations Y = Yh + Yp Y = Yzsr + Yzir The Attempt at a Solution I can't find...
16. ### Black hole traveling near the speed of light

Suppose a black hole travels at something like v = 0.999999999c relative to some observer. Does the black hole's event horizon becomes length contracted, thus appearing to turn into a black disk?
17. ### Length contraction hw problem

Homework Statement A relativistic conveyor belt is moving at speed 0.5c relative to frame S.Two observers standing beside the belt, 10 ft apart as measured in S, arrange that each will paint a mark on the belt at exactly the same instant (as measured in S). How far apart will the marks...
18. ### Circles vs an infinitely n-sided polygon.

Suppose you have a square, and you simply start increasing the number of vertices and edges proportionally, all the way to infinity. What, exactly, distinguishes this infinitely sided polygon from a circle? Logically, an infinitesimal edge would be like a point on a circle, although I...
19. ### Engineering Phasor circuit

Homework Statement Find the voltage Vo using node voltage method specifically. Homework Equations The Attempt at a Solution I am able to get the correct answer when finding the equivalent impedance, then determining the current, and then finding the voltage at the first node V1 by...
20. ### How is it that black holes can have angular momentum?

It's confusing to me how black holes can conserve angular momentum in relativity. In order to define rotation, there needs to be a 1 dimensional line that represents a radius. Considering that a black hole singularity has no dimensions, it seems impossible that a singularity, and hence a black...
21. ### Merging the strong force with the gravitational force

has anyone tried to merge gravity and the strong force mathematically? The two seem very compatible--the gloun is the only vector boson capable of causing a force to be applied between two similarly charged objects. Isn't it likely that there is some kind of gluonic field, which behaves...
22. ### Does the vacuum of space have finite electrical resistance?

Air typically has a very high but non zero resistance. Given that air is just a medium, and that space is also just a medium, does the vacuum of space have a fundamental constant of electrical resistance, or is the electrical resistance of space truly infinite? How is this proven one way or the...
23. ### How can a magnetar exist?

I'm confused how a magnetar could exist, given that the point of a neutron star is that electrons are compressed enough to combine with protons, thus leading to neutrons. If all the electrons were "used up" how could there be any currents, especially since neutrons can't conduct current anyways...
24. ### The limit of gravitational pull across a large distance

I was wondering if a gravitic field has a limit, where after a certain distance, determined by the properties of the structure creating the gravity field, the force felt by the 1kg masses becomes 0N. For example, will two 1 kg masses, seperated by an arbitrarily super large value (I.E. 50...
25. ### De broglie wavelength and lorentz contraction

Am I correct in thinking that the quantum mechanical de broglie wavelength explains relativity's contraction of matter? because lambda = h/p, as the velocity of say a proton increases, the momentum also increases, and the wavelength should get smaller because lim p-->infinity of h/p = 0. At very...
26. ### Black hole angular velocity

Could a small blackhole achieve an angular velocity such that the centripetal force is >= gravity, which would expand it enough to turn into a quark star or neutron star? I realize that in order to rotate the blackhole further, more mass must be added that will increase the amount of centripetal...
27. ### Quantum entanglement hinting at the nature of reality?

Citing a recent post from Dr. Chinese, it seems like quantum entanglement experiments are showing something beyond the current standard model. https://www.physicsforums.com/showthread.php?t=637454 If particles can be entangled to other particles that only existed in the past, it seems that it...
28. ### Higgs field expansion

Assuming the higgs field expands at the speed of light, the radius of the higgs field (all of spacetime actually) should be the age of the universe multiplied by the speed of light. 14.6 billion (4.6*10^17 seconds) * 299,792,458 m/s = 1.38 * 10^26 meters. The spherical volume of spacetime is...
29. ### Higgs field idea and gravity

I'm just throwing out an idea, which is probably wrong since I don't have a physics degree, but I'm curious anyways. I'd appreciate anyone giving feedback. For starters, I've read that the higgs mechanism, which gives all particles mass, is a paradigm of the meissner effect for superconductors...
30. ### Gravitational and movement related time dilation

Consider a massive object moving close to the speed of light. Imagine it travels close to a blackhole, but does not enter the blackhole. How do you calculate the exact time dilation experienced by the massive object's reference frame? How does time dilation due to movement stack with...