Thread: Atheists Lose 1, Deists Gain 1

Originally Posted by M21Sniper

"Relativistic mass is always conserved, it's a constant."

So you are saying the above statement is incorrect then?

What they are calling the "relativistic mass" is really the relativistic four-momentum. Classical momentum (p=mv) is not conserved for velocities close to c (the speed of light). Relativistic momentum ( E/c + p) is conserved.

What they are discussing are the conserved quantities for Lorentz transforms. Lorentz transforms are used to translate what one observer sees relative to another observer moving at velocities close to c.

They are not discussing particle physics, although particle physics does make use of the Lorentz transform.

As far as the Quantum mechanics and FTL travel, what i was referring to is this:

If you take matched particles, and you seperate them by a trillion miles, and spin one of the particles clockwise, the other particle will do the same(or maybe it was the reverse) instantly. Hawking did an excellent job of describing it in his sequel to a brief history of time, but it's been many years since i read it, so the details are beyond my recollection.

Care to fill in the blanks for me?

"What they are calling the "relativistic mass" is really the relativistic four-momentum. Classical momentum (p=mv) is not conserved for velocities close to c (the speed of light). Relativistic momentum ( E/c + p) is conserved.

What they are discussing are the conserved quantities for Lorentz transforms. Lorentz transforms are used to translate what one observer sees relative to another observer moving at velocities close to c.

They are not discussing particle physics, although particle physics does make use of the Lorentz transform."

So then you are agreeing with the statement that relativistic mass is conserved. LOL, damned eggheads, can never get a yes or no out of you folks.

PS...the term 'egghead' should not be taken as an insult, it is not meant in that way.

Originally Posted by M21Sniper

As far as the Quantum mechanics and FTL travel, what i was referring to is this:

If you take matched particles, and you seperate them by a trillion miles, and spin one of the particles clockwise, the other particle will do the same(or maybe it was the reverse) instantly. Hawking did an excellent job of describing it in his sequel to a brief history of time, but it's been many years since i read it, so the details are beyond my recollection.

Care to fill in the blanks for me?

That's "action at a distance", not FTL travel.

Think of the double slit experiment as a comparison: one of the colloquial interpretations of the double slit experiment is that particles moving through the slit "know something" about their future. While not 100% wrong in words, it doesn't necessarily imply anything about Time Travel.

-dale

ON MATCHED PARTICLES(BTW, is that the correct term?):

well it's obviously action at a speed far in excess of the speed of light, as light would take years to travel between the particles, yet they interact INSTANTLY despite the distance, which could be infinite.

Hawking said it proved the possibility of warping space-time to achieve FTL(or rather instantaneous) travel between two points. He seemed to be of the opinion that the particles 'know something' about eachother because they were connected, but that they take a 'short cut'.

He also said that the power required to operate a transport device suitable for something that we'd find useful would be more than all of the power generated throughout the HISTORY of mankid, and would require mathematical equations and technological developments that we're centuries from validating.

Originally Posted by M21Sniper

It is my understanding that the uncertainty principle means that the very act of measuring a particle affects it's actual position, hence the act of measuring it prevents one from accurately determining it's actual velocity/momentum.

That is a reasonably accurate description. Momentum and position are what is known as "conjugate variables" that cannot be simultaneously measured with better accuracy than Plancks constant, h. Energy and time are also conjugate variables.

The uncertainty principle is part of the theory of quantum mechanics. It is used to make predictions about the results of observations of quantum mechanical objects. It has been empirically proven.

Here's a quote from Heisenberg:

"The more precisely the POSITION is determined, the less precisely the MOMENTUM is known in this instant, and vice versa."

It's a paradox that so far as i know has never been resolved satisfactorilly.

But it would not surprise me if i misunderstand it at some level, as i was an infantryman, and we grunts are not exactly noted for our mathematical prowess.

LOL

Not bad for any infantryman .

Yes it is a paradox to our minds. Or at least, it does not agree with our intuition. But a lot of physics does not agree with our intuition. It can be very humbling. Quantum Mechanics works very well. People have worked very hard to "bust" QM with experiments which prove it wrong, but QM wins everytime.

However, as Richard Feynman said, "General relativity isn't really that hard to understand. Many scientists understand it. However, it is safe to say that no one understands Quantum Mechanics".

No one knows why quantum mechanics works. We do not understand why very small things behave the way they do. But we do understand how they behave very well.

Maybe someday someone will bust QM, but so far, it looks very hard to do.

But IN ENGLISH, tell me where i'm going astray. If Steven Hawking can 'dumb it down' enough for me to understand, i'm sure you can too

It is hard to describe physics well in plain english. And the concepts are tough; like mental weightlifting. General Relativity is like benching 500 with your brain. I am glad to see that you are curious enough to look into this stuff.

You might try Brian Green's books, "The Fabric of the Cosmos" or "The Elegant Universe". He is a very good explainer and uses plain english.

"You might try Brian Green's books, "The Fabric of the Cosmos" or "The Elegant Universe". He is a very good explainer and uses plain english."

Will do.

I love unsolvable puzzles that humble people a lot smarter than me.

"No one knows why quantum mechanics works. We do not understand why very small things behave the way they do. But we do understand how they behave very well."

You just said what i was trying to say when i said:

"And most of quantum mechanics is utterly unproven."

Ie, while we know what the particles will do, Heisenbergs principle of uncertainty prevents us from knowing why, which is basicly what you just said a lot better than i was trying to...

Originally Posted by M21Sniper

And as far as photons having no mass:

"The uncertainty principle was not accepted by everyone. Its most outspoken opponent was Einstein. He devised a challenge to Niels Bohr which he made at a conference which they both attended in 1930. Einstein suggested a box filled with radiation with a clock fitted in one side. The clock is designed to open a shutter and allow one photon to escape. Weigh the box again some time later and the photon energy and its time of escape can both be measured with arbitrary accuracy. Of course this is not meant to be an actual experiment, only a 'thought experiment'.

Niels Bohr is reported to have spent an unhappy evening, and Einstein a happy one, after this challenge by Einstein to the uncertainty principle. However Niels Bohr had the final triumph, for the next day he had the solution. The mass is measured by hanging a compensation weight under the box. This is turn imparts a momentum to the box and there is an error in measuring the position. Time, according to relativity, is not absolute and the error in the position of the box translates into an error in measuring the time.

Although Einstein was never happy with the uncertainty principle, he was forced, rather grudgingly, to accept it after Bohr's explanation. "

http://www-groups.dcs.st-and.ac.uk/~...ge_begins.html

Obviously Einstein and Bohr disagree with your assertion.

No they wouldn't. A photon has energy but no rest mass. Before the photon leaves the box, it's energy contributes to the rest mass of the box. When the photon leaves the box, it takes away energy, making the box less massive and therefore lighter.

But the photon has no rest mass. If it did have rest mass it would have infinite energy . Any mass going the speed of light has infinite energy, which is why masses must always go slower that the speed of light.

Originally Posted by dalem

That's "action at a distance", not FTL travel.

Think of the double slit experiment as a comparison: one of the colloquial interpretations of the double slit experiment is that particles moving through the slit "know something" about their future. While not 100% wrong in words, it doesn't necessarily imply anything about Time Travel.

-dale

except that you can then transfer information FTL

"No they wouldn't. A photon has energy but no rest mass. Before the photon leaves the box, it's energy contributes to the rest mass of the box. When the photon leaves the box, it takes away energy, making the box less massive and therefore lighter.

But the photon has no rest mass. If it did have rest mass it would have infinite energy . Any mass going the speed of light has infinite energy, which is why masses must always go slower that the speed of light."

Hmmm, now that's interesting. How can anything have energy without mass?

Kinetic Energy is determined by multiplying mass x velocity ^2 /2. If you have 186,000 miles per second of velocity, but no mass, how can you have any kinetic energy?

And if a photon takes away rest mass as it leaves, what happens to the mass it takes?

Hook a brother up with some answers.

Originally Posted by M21Sniper

I love unsolvable puzzles that humble people a lot smarter than me.

They are not necessarily smarter, they have just been at it longer than you.

"No one knows why quantum mechanics works. We do not understand why very small things behave the way they do. But we do understand how they behave very well."

You just said what i was trying to say when i said:

"And most of quantum mechanics is utterly unproven."

Quantum Mechanics IS proven. At least it is empirically proven as well as any theory in science. But we do not understand why it works. Why do particles act like waves? If an electron is a wave, how can it possible be a particle? How can a particle make an interference pattern?

Consider a caveman who walks into a modern house. He flips a switch and miraculously (to him) a light comes on. He can't believe it. So he flips the switch again and again and still the light comes on. So he has "proven" that the switch makes the light go on. But he has no idea WHY.

That is quantum mechanics.

"That is quantum mechanics."

More specifically, and what i was trying to get at, is that the caveman(us) can't prove why.

We know it works, we THINK we MAY know why some of it works, but we can't prove it because of Heisenberg's uncertainty principle.

Hence while we know it works we can't prove it...it just does.

LOL.

Originally Posted by M21Sniper

"No they wouldn't. A photon has energy but no rest mass. Before the photon leaves the box, it's energy contributes to the rest mass of the box. When the photon leaves the box, it takes away energy, making the box less massive and therefore lighter.

But the photon has no rest mass. If it did have rest mass it would have infinite energy . Any mass going the speed of light has infinite energy, which is why masses must always go slower that the speed of light."

Hmmm, now that's interesting. How can anything have energy without mass?

Kinetic Energy is determined by multiplying mass x velocity ^2 /2. If you have 186,000 miles per second of velocity, but no mass, how can you have any kinetic energy?

And if a photon takes away rest mass as it leaves, what happens to the mass it takes?

Hook a brother up with some answers.

Consider a wave traveling through the ocean. It passes through the mass of the ocean, but it has no mass of its own. But it sure has a lot of energy and momentum, as any surfer will tell you. It is not entirely accurate to think of light waves (photons) in the same way, but it is close.

The energy of a wave is proportional to it's frequency. The higher the frequency the higher the energy. For photons, E = h * f (roughly), where f is the frequency and h is Planck's constant again. The momentum is p = h/w, where I have used w for the wave length. That bloody "h" shows up everywhere in QM.

Mass is not conserved. Neither are the number of photons.

Originally Posted by M21Sniper

"That is quantum mechanics."

More specifically, and what i was trying to get at, is that the caveman(us) can't prove why.

Yes. We can prove QM works, but we don't know why. That's OK, we don't know why Gravity works either. As Feynman said,

"The ancients in their ignorance believed angels pushed the planets around the sun. We now know better. The angels push the planets towards the sun".

We know it works, we THINK we MAY know why some of it works, but we can't prove it because of Heisenberg's uncertainty principle.

There are mysteries in quantum mechanics far more bizarre than Heisenberg's uncertainty principle. The deeper you get in QM, the stranger it gets.

That's all I have time for now, gotta run. Good chatting with you.


LOL.[/QUOTE]