New Giant Hole in the Universe

[rhinefire]

Scientitists have uncovered a huge "hole" or void in the universe measuring some six trillion miles in size. Apparently there is absolutley nothing there! There are other such voids but this is the biggest so far.

Astronomers Find Enormous Hole in the Universe

 

[TOJ]

Scientitists have uncovered a huge "hole" or void in the universe measuring some six trillion miles in size. Apparently there is absolutley nothing there! There are other such voids but this is the biggest so far.

It's located ~39N ~77W and it sucks everything in and destroys it. :lol:

Sorry, couldn't resist. :2wave:

 

[rhinefire]

But you bring up a fact on this hole. This is not a "black hole" and it sucks nothing in like a black hole does. It is instead, just a void.

 

[black wolf]

But you bring up a fact on this hole. This is not a "black hole" and it sucks nothing in like a black hole does. It is instead, just a void.

It is God by definition

 

[Binary_Digit]

That's really cool, but something about the report really bugs me.

Astronomers have found an enormous hole in the Universe, nearly a billion light-years across, empty of both normal matter such as stars, galaxies, and gas, and the mysterious, unseen "dark matter."

(snip)

When the photons pass through an empty void, they lose a small amount of energy from this effect, and so the CMB radiation passing through such a region appears cooler.

Supposedly there is no dark matter in this "hole", but yet light can still propagate through it. Electromagnetic waves such as light cannot propagate unless electrons are present. So if light is passing through this hole, then dark matter does exist there.

I never understood how physicists can invent a zero-mass particle like the photon and claim that light is the only electromagnetic wave that has them or anything like them. Photons don't propagate, waves do. I don't even think photons physically exist. How can something exist if it has zero mass?

 

[TOJ]

But you bring up a fact on this hole. This is not a "black hole" and it sucks nothing in like a black hole does. It is instead, just a void.

That still would be centered at 39N 77W. That location is a big nothing. :lol:

On a more serious note;

"What we've found is not normal, based on either observational studies or on computer simulations of the large-scale evolution of the Universe," Williams said.

I find it strange that they would be surprised. Its a danm big place and our observational studies capibilities are rather limited.

I do love it when people are surprised that computer models do not predict something or predict something that is totally wrong. Models are only as good as the data going in and the algorithms that manipulate it. The subject-matter experts are going to advise the analysts and programmers based on thier knowledge and beliefs. If they did not expect it, they probably did not give the development team information that would have allowed them to create software to predicted it.

Interesting read though.

 

[new coup for you]

it's obviously Unicron

 

[Binary_Digit]

I do love it when people are surprised that computer models do not predict something or predict something that is totally wrong. Models are only as good as the data going in and the algorithms that manipulate it. The subject-matter experts are going to advise the analysts and programmers based on thier knowledge and beliefs. If they did not expect it, they probably did not give the development team information that would have allowed them to create software to predicted it.

That's exactly right and I think it's funny too! :2razz:

 

[jfuh]

That's really cool, but something about the report really bugs me.

Astronomers have found an enormous hole in the Universe, nearly a billion light-years across, empty of both normal matter such as stars, galaxies, and gas, and the mysterious, unseen "dark matter."

(snip)

When the photons pass through an empty void, they lose a small amount of energy from this effect, and so the CMB radiation passing through such a region appears cooler.

Supposedly there is no dark matter in this "hole", but yet light can still propagate through it. Electromagnetic waves such as light cannot propagate unless electrons are present. So if light is passing through this hole, then dark matter does exist there.

I never understood how physicists can invent a zero-mass particle like the photon and claim that light is the only electromagnetic wave that has them or anything like them. Photons don't propagate, waves do. I don't even think photons physically exist. How can something exist if it has zero mass?

Who said that photons have zero mass? Zero rest mass is not the same as having zero mass.

 

[Binary_Digit]

Who said that photons have zero mass? Zero rest mass is not the same as having zero mass.

"Does light have mass? The short answer is "no", but it is a qualified "no" because there are odd ways of interpreting the question which could justify the answer "yes".
Light is composed of photons, so we could ask if the photon has mass. The answer is then definitely "no": the photon is a massless particle. According to theory it has energy and momentum but no mass, and this is confirmed by experiment to within strict limits."

http://math.ucr.edu/home/baez/physics/Relativity/SR/light_mass.html

 

[jfuh]

"Does light have mass? The short answer is "no", but it is a qualified "no" because there are odd ways of interpreting the question which could justify the answer "yes".
Light is composed of photons, so we could ask if the photon has mass. The answer is then definitely "no": the photon is a massless particle. According to theory it has energy and momentum but no mass, and this is confirmed by experiment to within strict limits."

Does light have mass?

One can only still state that it's a zero resting mass.

 

[Binary_Digit]

"Does light have mass? The short answer is "no", but it is a qualified "no" because there are odd ways of interpreting the question which could justify the answer "yes".
Light is composed of photons, so we could ask if the photon has mass. The answer is then definitely "no": the photon is a massless particle. According to theory it has energy and momentum but no mass, and this is confirmed by experiment to within strict limits."

Does light have mass?

One can only still state that it's a zero resting mass.

If it has momentum how is it resting?

 

[jfuh]

If it has momentum how is it resting?

As is in your source as well. momentum p = mv or mass times velocity. So when a photon is with zero velocity it has zero momentum and zero resting mass.

 

[Binary_Digit]

"According to theory it has energy and momentum but no mass"

The way this is worded, even when it has momentum it still has no mass.

"Quantum mechanics introduces the idea that light can be viewed as a collection of "particles"--photons. Even though these photons cannot be brought to rest, and so the idea of rest mass doesn't really apply to them, we can certainly bring these "particles" of light into the fold of equation (1) by just considering them to have no rest mass."

What is the mass of a photon?

The way this is worded, it's not possible for a photon to be resting.

Am I misinterpreting these?

 

[jfuh]

"According to theory it has energy and momentum but no mass"

The way this is worded, even when it has momentum it still has no mass.

"Quantum mechanics introduces the idea that light can be viewed as a collection of "particles"--photons. Even though these photons cannot be brought to rest, and so the idea of rest mass doesn't really apply to them, we can certainly bring these "particles" of light into the fold of equation (1) by just considering them to have no rest mass."

What is the mass of a photon?

The way this is worded, it's not possible for a photon to be resting.

Am I misinterpreting these?

The statement that photons can not be brought to rest - this is untrue. Not only can they be brought to a standstill, they have been.Source
The variance is that you must look at the semantics of what is defined as mass. Rest mass vs relative mass. The mass of photons is not the classical newtonian mass we see in F=mA. It has to do with the theory of relativity in which mass is gained with regards to speed - the reason why the universal speed limit is the speed of light because it will require infinite amount of energy in order to accelerate a true particle to such a speed because it's mass is ever gaining with speed.
So the definition as to a resting mass of a photon.
This answers a lot.

E = mrelc2 , and also E2 = p2c2 + m2restc4 . (1) There are two interesting cases of this last equation:

1. If the particle is at rest, then p = 0, and E = mrestc2.
2. If we set the rest mass equal to zero (regardless of whether or not that's a reasonable thing to do), then E = pc.

 

[Binary_Digit]

Now I'm even more confused.

"Even before it was known that light is composed of photons, it was known that light carries momentum and will exert pressure on a surface. This is not evidence that it has mass since momentum can exist without mass."

Momentum can exist without mass??

p = mv
p = 0 * v
p = 0

I don't know who comes up with this stuff, but I think they've had too many hits from the quantum bong.

 

[Binary_Digit]

The statement that photons can not be brought to rest - this is untrue. Not only can they be brought to a standstill, they have been.Source

Cool, that confirms my recent suspicion that the source I was reading has a couple of screws loose.

The variance is that you must look at the semantics of what is defined as mass. Rest mass vs relative mass. The mass of photons is not the classical newtonian mass we see in F=mA. It has to do with the theory of relativity in which mass is gained with regards to speed - the reason why the universal speed limit is the speed of light because it will require infinite amount of energy in order to accelerate a true particle to such a speed because it's mass is ever gaining with speed.
So the definition as to a resting mass of a photon.
This answers a lot.
[/list]

Relative mass implies that the photon is an isotope doesn't it? I.e. it has neutrons and protons. It's the particle's mass relative to carbon-12. So photons have neutrons and protons too?

 

[jfuh]

Cool, that confirms my recent suspicion that the source I was reading has a couple of screws loose.

Their mathematicians, what did you expect?:lol:

Relative mass implies that the photon is an isotope doesn't it? I.e. it has neutrons and protons. It's the particle's mass relative to carbon-12 AFAIK.

No, not an isotope. Isotope would be the addition of particles, the relative mass of a particle is the variance between it under varied conditions. Particles gain mass as they accelerate in a similar way to time being relative also with speed. Faster moving objects exhibit slower time than slower moving object. Similarly faster moving objects exhibit greater mass than do slower moving objects.

 

[jfuh]

Now I'm even more confused.

"Even before it was known that light is composed of photons, it was known that light carries momentum and will exert pressure on a surface. This is not evidence that it has mass since momentum can exist without mass."

Momentum can exist without mass??

p = mv
p = 0 * v
p = 0

I don't know who comes up with this stuff, but I think they've had too many hits from the quantum bong.

Yes because momentum is energy that is related to mass.

 

[Binary_Digit]

Yes because momentum is energy that is related to mass.

Right, and it's represented by that formula:

p = m * v

If a particle without mass (m = 0) has momentum, then according to the formula that momentum has to be zero:

p = 0 * v
p = 0

Which means it doesn't have momentum after all doesn't it?

More confusion from Wiki (in bold):

"The invariant mass of an object (also known as the rest mass, intrinsic mass or proper mass) is an observer-independent quantity that is synonymous with mass. On the other hand, the relativistic mass of an object (also known as apparent mass) increases with its speed and therefore depends on one's frame of reference. The concept of relativistic mass has gradually fallen into disuse in physics since 1950[citation needed], when particle physics showed the relevance of invariant mass, to the point that relativistic mass is rarely used in 2007 scientific research literature.

(snip)

Relativistic mass and rest mass (invariant mass) are both traditionally used concepts in physics. However, with the development of Minkowskifour-vector notation and general relativity, physicists gradually concluded that the invariant mass is the more fundamental quantity in the theory of relativity, and that the relativistic mass is just a redundant expression for total energy. "

Mass in special relativity - Wikipedia, the free encyclopedia

It says relativistic mass and rest mass are not the same kind of mass. So when they talk about a photon having zero rest mass, doesn't that pertain to its invariant mass, not its relativistic (speed) mass?

I appreciate the conversation BTW, I've wanted to debate this with a knowledgeable person for a long time. Here's my understanding. Light is an electromagnetic wave just like any other, the only difference is the frequency range. In order for a light wave to travel from point A to point B, the proper kind of medium needs to exist between them (electrons, other conditions). This is true for electromagnetic waves from ~1MHz all the way up to gamma rays. Yet light is the only electromagnetic wave that emits a photon. That seems suspicious to me. Light waves supposedly emit these photons out of thin air, which is also suspicious and probably explains why they have to be defined with zero mass in order for their formulas to work. Mass is energy and you can't create energy out of thin air. I read somewhere that they've actually seen photons in laboratories, but I think they actually saw harmonics or some other wave phenomenon. What are your thoughts on that?

 

[Cold Highway]

it's obviously Unicron

ROFL transformers referrence I wonder who would win between him and Galactus.

 

[jfuh]

Right, and it's represented by that formula:

p = m * v

If a particle without mass (m = 0) has momentum, then according to the formula that momentum has to be zero:

p = 0 * v
p = 0

Which means it doesn't have momentum after all doesn't it?

More confusion from Wiki (in bold):

"The invariant mass of an object (also known as the rest mass, intrinsic mass or proper mass) is an observer-independent quantity that is synonymous with mass. On the other hand, the relativistic mass of an object (also known as apparent mass) increases with its speed and therefore depends on one's frame of reference. The concept of relativistic mass has gradually fallen into disuse in physics since 1950[citation needed], when particle physics showed the relevance of invariant mass, to the point that relativistic mass is rarely used in 2007 scientific research literature.

(snip)

Relativistic mass and rest mass (invariant mass) are both traditionally used concepts in physics. However, with the development of Minkowskifour-vector notation and general relativity, physicists gradually concluded that the invariant mass is the more fundamental quantity in the theory of relativity, and that the relativistic mass is just a redundant expression for total energy. "

Mass in special relativity - Wikipedia, the free encyclopedia

It says relativistic mass and rest mass are not the same kind of mass. So when they talk about a photon having zero rest mass, doesn't that pertain to its invariant mass, not its relativistic (speed) mass?

I appreciate the conversation BTW, I've wanted to debate this with a knowledgeable person for a long time. Here's my understanding. Light is an electromagnetic wave just like any other, the only difference is the frequency range. In order for a light wave to travel from point A to point B, the proper kind of medium needs to exist between them (electrons, other conditions). This is true for electromagnetic waves from ~1MHz all the way up to gamma rays. Yet light is the only electromagnetic wave that emits a photon. That seems suspicious to me. Light waves supposedly emit these photons out of thin air, which is also suspicious and probably explains why they have to be defined with zero mass in order for their formulas to work. Mass is energy and you can't create energy out of thin air. I read somewhere that they've actually seen photons in laboratories, but I think they actually saw harmonics or some other wave phenomenon. What are your thoughts on that?

Whew, a lot of good questions, some misconceptions but generally the right track. I'll get back to you and try to best answer these.

 

[new coup for you]

ROFL transformers referrence I wonder who would win between him and Galactus.

Galactus doesnt have the power of Orson Welles

 

[jfuh]

Right, and it's represented by that formula:

p = m * v

If a particle without mass (m = 0) has momentum, then according to the formula that momentum has to be zero:

p = 0 * v
p = 0

Which means it doesn't have momentum after all doesn't it?

What you're missing is that P is a unit of energy, hence what you've have incorrectly inserted is already the assumption that the mass of the photon is 0. The p of a photon is already set it's already a real value, what you're trying to determine is not what p is equal to, nor are you trying to determine the classical definition of m which is resting mass. We've already established that there is a realative mass with objects moving at various speeds. Here we know that v = c the speed of light and whatever p is already equal to we can solve for the m-relative. How do we determine p without measuring the mass? Because we would know the wavelegth and the frequency of the photon already with E=lambda x f
Also as has been emphasized we are looking at the relative mass. Hence the equation to use is thus

More confusion from Wiki (in bold):

"The invariant mass of an object (also known as the rest mass, intrinsic mass or proper mass) is an observer-independent quantity that is synonymous with mass. On the other hand, the relativistic mass of an object (also known as apparent mass) increases with its speed and therefore depends on one's frame of reference. The concept of relativistic mass has gradually fallen into disuse in physics since 1950[citation needed], when particle physics showed the relevance of invariant mass, to the point that relativistic mass is rarely used in 2007 scientific research literature.

(snip)

Relativistic mass and rest mass (invariant mass) are both traditionally used concepts in physics. However, with the development of Minkowskifour-vector notation and general relativity, physicists gradually concluded that the invariant mass is the more fundamental quantity in the theory of relativity, and that the relativistic mass is just a redundant expression for total energy. "

Mass in special relativity - Wikipedia, the free encyclopedia

Ho boy, Minkowskifour-vector......

It says relativistic mass and rest mass are not the same kind of mass. So when they talk about a photon having zero rest mass, doesn't that pertain to its invariant mass, not its relativistic (speed) mass?

Yes that's right, they are not the same kind of mass

I appreciate the conversation BTW, I've wanted to debate this with a knowledgeable person for a long time. Here's my understanding. Light is an electromagnetic wave just like any other, the only difference is the frequency range.

Not quite - strictly speaking the only variance is that we see "light" all other wavelengths within the EM spectrum are also light and bend, refract, reflect in the same behavior way as "light" does - even travel at the same velocity. It's the wavelengths that differ, not so much the frequency.

In order for a light wave to travel from point A to point B, the proper kind of medium needs to exist between them (electrons, other conditions). This is true for electromagnetic waves from ~1MHz all the way up to gamma rays. Yet light is the only electromagnetic wave that emits a photon. That seems suspicious to me. Light waves supposedly emit these photons out of thin air, which is also suspicious and probably explains why they have to be defined with zero mass in order for their formulas to work. Mass is energy and you can't create energy out of thin air. I read somewhere that they've actually seen photons in laboratories, but I think they actually saw harmonics or some other wave phenomenon. What are your thoughts on that?

Well as with the Nature article I gave you, what they did was literally freeze the photon and "saw" the photon. Light can travel even without any medium. You can suck everything out of a sealed chamber and "light" still travels through the vacuum without any difficulty. Sound waves are what must need a medium.

 

[TheNextEra]

So basically they have discovered the Universe's ***_hole, nice :mrgreen: