Any astrophysicist or anyone that know about it want to answer a few questions?

[Anvilbrother 0]

I consider myself to be someone who has a general grasp of what the cosmos is made up of but there are lots of topics that I am still not clear on. Here are a few

If a photon is massless how can a box containing light weigh more than the same box empty.

If mass and gravity are linked why can't the same photon not be able to escape the event horizon or the Schwarzschild radius? How is the hole attaining attraction or pull?

Also how can a black hole "evaporate" by hawking radiation if nothing escapes them? It would seem that even the shedding off one part of a particle-antiparticle pair would add mass to the hole even though one escaped. Unless the fact that it has to be negatively charged due to preserving total energy is the key to the whole part im confused!

Also I understand mass can create energy and energy can create mass, what kind of energy is theorized to have created gravity, electromagnetism, strong nuclear, and weak nuclear forces nanoseconds after the "big bang"? Something had to be there before right? Such as the mass from a super massive black hole that evaporated to the point it did not have enough gravity to contain the mass?

One about stars is that usually when huge stars over 5 stellar masses dies it can go through gravitational collapse and turn into neutron star, or go supernova and can can possibly go black hole after. What factors decide which way it will go? Is it the amount of mass left over after expansion and contraction?

Also what are your thoughts on the creation of MBH in the LH collider that is supposed to come on line this year? I have heard that there could be black holes created every second along with the possibility of strangelets!?

/nerd
//:)

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[StreetScooby 5]

Quote

If a photon is massless how can a box containing light weigh more than the same box empty.

Photons are not massless.

Quote

Also what are your thoughts on the creation of MBH in the LH collider that is supposed to come on line this year? I have heard that there could be black holes created every second along with the possibility of strangelets!?

That has about the same probability as the collider creating a huge dragon that eats NYC (...I actually read that somewhere).

We are all engines of karma

[Anvilbrother 0]

Nasa says photons are massless
NASA

But in finding that I did find a good answer to my question. Photons don't respond to the gravity we know they respond to the altering of time space fabric.

(taken from nasa answer to question)
General relativity explained, in a consistent way, how gravity affects light. We now knew that while photons have no mass, they do possess momentum. We also knew that photons are affected by gravitational fields not because photons have mass, but because gravitational fields (in particular, strong gravitational fields) change the shape of space-time. The photons are responding to the curvature in space-time, not directly to the gravitational field. Space-time is the four-dimensional "space" we live in -- there are 3 spatial dimensions (think of X,Y, and Z) and one time dimension.

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[DoubleH 0]

If i recall correctly Photons only have zero rest mass. You and everything else in the universe increases in mass as you increase velocity, up to infinite mass at the speed of light.
Gravity does affect photons too, or at least it bends space time so that they follow a straight path through curved space.
Black holes can evaporate because beyond the event horizon there is still a possibility that a particle can escape the black holes gravity. When a particle and an anti particle come into existence they usually anhilliate each other immediately but should they come into existance either side of the event horizon, one will be pulled into the singularity but the other can escape the black hole. The one that escapes is seen as hawking radiation. I think thats right but i may not be 100%

[billeisele 130]

Quote

I consider myself to be someone who has a general grasp of what the cosmos is made up of but there are lots of topics that I am still not clear on. Here are a few

If a photon is massless how can a box containing light weigh more than the same box empty.

/nerd
//:)

this didn't make sense to me so I tried an experiment and found that a box containing light and a box containing dark weighed the same

Give one city to the thugs so they can all live together. I vote for Chicago where they have strict gun laws.

[CSpenceFLY 1]

You came to DZ.com for the answers to these questions?? Let me be the first to say Boobies!!

[ryoder 1,590]

Quote

this didn't make sense to me so I tried an experiment and found that a box containing light and a box containing dark weighed the same

If you have a box of dark handy, then maybe you can answer this question: What is the speed of dark?

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[Anvilbrother 0]

Ok so photons have a zero rest mass, but mass increases with velocity. I thought photons are alway in motion at 299,792,458m/s ie their speed(light)? lol So how could they have a rest mass?

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[Anvilbrother 0]

I'm practicing to baffle my friends with bullshit for when I need do it to my boss! lol

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[jcd11235 0]

Quote

If a photon is massless how can a box containing light weigh more than the same box empty.

Perhaps the box filled with light is moving at a speed near the speed of light, while the box without light is a system at rest.

Math tutoring available. Only $6! per hour! First lesson: Factorials!

[JackC 0]

Quote

If a photon is massless how can a box containing light weigh more than the same box empty.

You can say that a photon has an equivalent mass given by m=hf/c^2 where h is Planck's constant, f is the frequency of the photon and c is the speed of light. Not that it's much use to say that.

Quote

If mass and gravity are linked why can't the same photon not be able to escape the event horizon or the Schwarzschild radius? How is the hole attaining attraction or pull?

The velocity needed to escape the gravitational pull of a massive object is related to its mass. Once you get to a critical mass, the escape velocity becomes larger than the speed of light and that's the critical mass of a black hole. The photon can't travel faster than the speed of light which isn't fast enough to escape the gravitational pull of the object.

Quote

Also how can a black hole "evaporate" by hawking radiation if nothing escapes them? It would seem that even the shedding off one part of a particle-antiparticle pair would add mass to the hole even though one escaped. Unless the fact that it has to be negatively charged due to preserving total energy is the key to the whole part im confused!

DoubleH answered that one, I'm fairly sure he's right.

Quote

Also I understand mass can create energy and energy can create mass, what kind of energy is theorized to have created gravity, electromagnetism, strong nuclear, and weak nuclear forces nanoseconds after the "big bang"? Something had to be there before right? Such as the mass from a super massive black hole that evaporated to the point it did not have enough gravity to contain the mass?

Energy and mass are related but I'm not sure it's right to say that energy creates mass and vice versa. As far as what kind of energy caused the four fundamental forces, well, fuctifino.

Quote

One about stars is that usually when huge stars over 5 stellar masses dies it can go through gravitational collapse and turn into neutron star, or go supernova and can can possibly go black hole after. What factors decide which way it will go? Is it the amount of mass left over after expansion and contraction?

The mass of the star is the critical factor I think but I don't really know about this one.

Quote

Also what are your thoughts on the creation of MBH in the LH collider that is supposed to come on line this year? I have heard that there could be black holes created every second along with the possibility of strangelets!?

Mass is not the same in all reference frames. A particle moving at a sufficiently high speed (high kinetic energy) will have a larger mass according to a static observer than it would have in it's own reference frame. So an electron with tiny mass in it's own reference frame would appear to have a huge mass if it whizzed past you fast enough. If it went fast enough it could have enough apparent mass to be called a black hole. But that's not the same as having a "real" black hole in the lab.

Strangelets (I think) are made of up, down and strange quarks. Quarks come in 6 flavours of which "up", "down" and "strange" are three of them. The standard model of particle physics assigns non-integer charges to quarks, and matter is assembled out of these components so that charge for the assembled particle adds up to an integer. Strangelets are one way of assembling quarks so that the maths adds up. So they should be theoretically allowed to exist, we just need a really big-ass particle accelerator to stick the parts together. It's a test to see if the Standard Model is right, cos it might not be (and probably isn't, but that's another story).

But it's late, I've had beer and that could be a load of bollocks. It's been a while since I did any of that stuff. Night night.

[chris-b 0]

Also I understand mass can create energy and energy can create mass, what kind of energy is theorized to have created gravity, electromagnetism, strong nuclear, and weak nuclear forces nanoseconds after the "big bang"? Something had to be there before right? Such as the mass from a super massive black hole that evaporated to the point it did not have enough gravity to contain the mass?

Thats what ive always thought. what if the universe stops expanding, then collapses back in on itself? maybe that is the only way to create an explosion enormous enough to spread all that matter out that we call the universe. then theres the fact that it may be an infinite repeating event. that could also be happening elsewhere...



One about stars is that usually when huge stars over 5 stellar masses dies it can go through gravitational collapse and turn into neutron star, or go supernova and can can possibly go black hole after. What factors decide which way it will go? Is it the amount of mass left over after expansion and contraction?

I would imagine it would have something to do with mass/density?

[billeisele 130]

Quote

Quote

this didn't make sense to me so I tried an experiment and found that a box containing light and a box containing dark weighed the same

If you have a box of dark handy, then maybe you can answer this question: What is the speed of dark?

that is an easy question, once i close the box the dark is trapped inside, right now the box is on the table so the speed is equivalent to the rotational speed of the earth

Give one city to the thugs so they can all live together. I vote for Chicago where they have strict gun laws.

[popsjumper 2]

I'm waiting to see what Chuck says about all this. He'll clarify it.


And...Bill, watch out...that box may have a leak in it and all your dark will escape. Then we'll ALL be running around in the dark...not just me.

My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

[Gene03 0]

Quote

I'm practicing to baffle my friends with bullshit for when I need do it to my boss! lol

Meditation.
Close your eyes in your quite space.
Empty your mind of all thought.
County by ones up to 169, (13x13).
Your questions will be answered.

Or then again, maybe naught.

“The only fool bigger than the person who knows it all is the person who argues with him.

Stanislaw Jerzy Lec quotes (Polish writer, poet and satirist 1906-1966)

[billeisele 130]

And...Bill, watch out...that box may have a leak in it and all your dark will escape. Then we'll ALL be running around in the dark...not just me.

no problem, sealed it good with duct tape
every once in a while i go in the bathroom where there are no windows, shut the door and slowly open the box just to make sure the dark is still in there - so far so good

Give one city to the thugs so they can all live together. I vote for Chicago where they have strict gun laws.

[billeisele 130]

Quote

And...Bill, watch out...that box may have a leak in it and all your dark will escape. Then we'll ALL be running around in the dark...not just me.

no problem, sealed it good with duct tape
every once in a while i go in the bathroom where there are no windows, shut the door and slowly open the box just to make sure the dark is still in there - so far so good

checked the box that was filled with light, snuck up on it this morning real quiet like, then pounced and ripped it open - yep still full of light - but now I need another box

Give one city to the thugs so they can all live together. I vote for Chicago where they have strict gun laws.

[Darius11 12]

I like this thread and all but just wanted to say dude your avatar is going to give me nightmares.

I'd rather be hated for who I am, than loved for who I am not." - Kurt Cobain

[skiskyrock 0]

Quote

Ok so photons have a zero rest mass, but mass increases with velocity. I thought photons are alway in motion at 299,792,458m/s ie their speed(light)? lol So how could they have a rest mass?

The speed of light in not a constant, it varies depending on the refractive index of the material. The speed of light in a vacuum is 299,792,458m/s The lowest speed of light I've heard of is in a bose-einstein condensate: 38 mph.

[skydemon2 0]

Quote

The speed of light in not a constant, it varies depending on the refractive index of the material. The speed of light in a vacuum is 299,792,458m/s The lowest speed of light I've heard of is in a bose-einstein condensate: 38 mph.

I read somewhere that you can slow light down even more with Relative Gravitational Wind.

Beauty is only skin deep, but ugly goes clean to the bone!

I like to start my day off with a little Ray of Soulshine™!!

[billeisele 130]

Quote

I like this thread and all but just wanted to say dude your avatar is going to give me nightmares.

as it should, this critter is worse than a bedbug

Give one city to the thugs so they can all live together. I vote for Chicago where they have strict gun laws.

[DontPanic 0]

Quote

Also I understand mass can create energy and energy can create mass, what kind of energy is theorized to have created gravity, electromagnetism, strong nuclear, and weak nuclear forces nanoseconds after the "big bang"?

Gravity is not energy. Gravity is the warping of space (according to the General Theory of Relativity). Having said that, you can artificially create gravity by merely applying a force to an object to accelerate it. According to Einstein, the force you feel in an elevator that is accelerating upwards is the same as gravity.

In fact, acceleration is what Einstein's General Theory of relativity was trying to address. Einstein's Special Theory of Relativity (which came first) covered the "special" case of constant velocity, but couldn't handle acceleration (i.e. a change in velocity). In expanding on his Theory of Relativity to cover acceleration, he showed that acceleration is the same thing as gravity.

Also, when looking at gravity early in the big bang, you have to consider that space hadn't quite unfolded yet. Although all the matter in the Universe was instantaneously created at t=0 in the first instant, space itself mostly unfolded during the inflationary epoch, which was a distinct period after t=0.

[Leapinglizardto 0]

i'm still working on the bunny ear thing with my shoelaces without help. sorry can't help you.

It's pretty pathetic when you have to TELL people you're fucking cool Skymama «narrative»This thread will lock in 3..2.. What a load of narrow-minded Xenophobic Bullshit!-squeak

[StreetScooby 5]

Nice explanation. Why the emphasis in physics (simply speaking) for a unifying theory of force and energy?

We are all engines of karma

[DontPanic 0]

Quote

Why the emphasis in physics (simply speaking) for a unifying theory of force and energy?

Well, I'm drunk enough to take a stab at that, but not so drunk as to make the answer completely unintelligible.

The fascination with unification theories started in the first half of the 20th century with Einstein and the classical/relativistic physicists squaring off against Heisenberg and the quantum physicists.

Classical/relativistic physics was able to accurately predict the behavior of many aspects of our Universe. Likewise, quantum physics was also able to accurately describe a different class of natural phenomenon. But classical/relativistic physics and quantum physics seemed to be fundamentally inconsistent. Classical/relativistic physics provided solutions that very mechanical, and the answers could be run backwards and forwards in time. Quantum physics is probability based, and could predict likely solutions going forward in time, but could not run a problem backwards in time.

And scientists were fascinated by a seemingly diabolical nature of the universe that would not let you structure a problem that would simultaneously pit classical/relativistic physics against quantum physics (such as wave/particle duality and the Heisenberg uncertainty principle).

Since that time, the conceptual understanding of physics has evolved with the development of the four fundamental forces (strong/weak/electromagnetic/gravity) and the Standard Model of particle physics. The Standard Model has a strong foundation in quantum physics, and does a good job of explaining three out of four of the fundamental forces, but still hasn't accounted for gravity.

So we're still left with two rather different sets of physics to explain the universe.