The Science Thread here

Originally posted by Arbitrageur
It depends on how you define perpetual motion.

Well a galaxy emits light into its surroundings right? And we can detect that light from 'very' far away. Is the light that is traveling millions of light years to our planet from those galaxies, doing work on that journey? The electric and magnetic wave transferring their energy to one another (if thats how light works), you are looking as that EM wave or photon as a system that loses no energy, therefore no work was done, even though it is 'using?' energy to traverse vast expanses of space. Or is it not using energy because an object placed in motion will remain in motion untill forced otherwise, light then being a bullet that cant slow down unless done so by something beyond it. How does light have different levels of energy, yet the same velocity? Are there wavelengths of light that travel further, faster then other wavelengths? If not, what is stopping that from occurring? Imagine a huge supernova or something that emits very high energy light compared to a flashlight. There was an intense force that jolted atoms, and very highly energetic light was emitted (if this is how it works...). So to create the high frequency the atom/electron/s were vibrated up and down violently in a relatively shorter up and down displacement, then if it were to have been a longer one, resulting in longer wavelengths(is that how it works?). So there is a speed limit, but its as if high frequency gets more cresty punches in, in the limited space-time of C, and thats why it is higher energy?

Also about atoms perpetual motion. The atom itself is made of quantities of waves and/or particles...values of energy so these parts of the atom must constantly interact with one another to keep the atom stable, so in a sense is the atom itself not an object of perpetual motion, if the parts that make it up, can expend energy (even if back and forth..if thats how it works) and remain an intact system?

Originally posted by an0nThinker
reply to post by Grimpachi

 

That is a good question and I want to try to answer it. Firstly, we will always remain sub light speed in regular travel. This is because of relativity, move really fast for long time and you risk leaving everyone behind as they age much faster than you. Because of this we will always remain at 5-10% of light speed.

What a real warp drive will be is bending space time ahead and behind the space ship. Work has already started on a prototype
Read this

Think of space time like a piece of paper, now start pushing the 2 ends together. If you bend the paper enough you'll find 2 bends almost touching. The distance between these 2 will be significantly less. This is what we are trying to do. The problem is energy, we need lots and lots of it. Maybe a high density LENR(cold fusion) or high efficiency and low weight fission reactor(possible with todays technology). We can discuss the physics behind it if you want. We are still decades away from even trying this stuff out and this will need significant investments.

edit on 10-6-2013 by an0nThinker because: fixing link

Thank you so much. That video was awesome. I understood a decent portion of what they were saying. The analogy of surfing a wave really helped. (I Surf) I would love to know more.

You brought up something I would really appreciate a better explanation for though which I had all but forgotten when talking about space travel and approaching the speed of light. How is it possible for time to move differently when traveling at near speed of light? I don’t understand that.

It does make me wish we had near speed of light travel available I would book a round trip voyage so when I got back I could be in the future with newer models like warp drive. I defiantly would.

reply to post by Grimpachi


The reason is time dilation. Quick example I am travelling on a space ship and you are my twin and stay on earth. We have the same clock, to us they both run the same however space time moves differently for us.

en.wikipedia.org...

Here you can calculate your own. Dialation is exponential. So as we approach c dilation becomes significant.
Example-
96.7% of c 1second moving = 4 seconds stationary
98.4% 1s= 6s
99.7 1s= 13s
99.9 1s = 22s
99.98 1s = 60s

keisan.casio.com...

reply to post by an0nThinker


I am reading the links but I am afraid this one is going to go over my head.

I will try to read them again later to see if something clicks for me.

Thanks

Originally posted by jiggerj

Good stuff, Semi.

What I find interesting is that I think an atom has a neutral center mass, with orbiting electrons that seem more like suns to me. In a living cell, the energy part (the mitochondria) is not in the center. So, why the reverse in the macroverse?

This is not entirely true. The electrons that surround an atom have a probability of existing in certain areas, as predicted by QM. I think you're referring to the very outdated Bohr model, which was phased out of popularity sometime in the early part of last century. The centre mass of an atom, the nucleus, is not neutral at all. It contains protons, which are positively charged, and neutrons, which are neutral and help glue the protons together. Electrons are negatively charged and this is what balances out the net charge of a given atom.

Electrons are negatively charged

reply to post by hypervalentiodine


Thanks for reminding me. No matter how many times I hear it I quickly forget it. Maybe it's because I don't understand what negatively charged means. Just recently I heard that car batteries are charged with negative electrons. Is that right? I'll have to do some research on the negative stuff.

Question: Could part of the reason why light travels at the velocity it does, is because it follows the geometry of expanding space? Or maybe light doesnt move at all, and it is just that all surrounding matter is moving through space at such a velocity, that when light is caused to appear, it is a still reference frame. So say lightning strikes and the surrounding area is filled with light. What im saying is; could it be possible that that light is filling a relatively small area of space very quickly, but this affect is intensified by the fact that the matter of our planet is traveling through space (relative to some non existent spatial backdrop?) some kind of smearing affect, like if I dropped a drop of food coloring in a bowl of water, and then moved the bowl of water laterally the food coloring i would expect to spread in some manner. But it would be more like the bowl of water already traveling on a very long treadmill, and then at some fixed point dropping a drop of food color in the bowl, but because a lightning strike is in the frame of reference with the traveling earth im not sure ?

Question: Could part of the reason why light travels at the velocity it does, is because it follows the geometry of expanding space? Or maybe light doesnt move at all, and it is just that all surrounding matter is moving through space at such a velocity,

reply to post by ImaFungi


Hi Ima, I can't answer your question, but I'd like to ask for a clarification if you don't mind. You make 'light' sound as though it's a non-physical thing. Now, correct me if I'm wrong, but isn't light made up of very real and very physical photons? So, when you say that maybe light doesn't move at all and the surrounding matter is moving through space, why would this not include photons?

reply to post by ImaFungi

Originally posted by jiggerj
So, when you say that maybe light doesn't move at all and the surrounding matter is moving through space, why would this not include photons?

In relativity the behavior of light is fundamentally unlike matter.

With matter, the velocity always depends on the reference frame.

With light, the velocity is always the same in every reference frame. It is a constant. This is why you can shine a light ahead of a spaceship going half the speed of light with respect to Earth, and both the observer on Earth as well as an observer on the spaceship will still see it going at the speed of light. Nobody will see it going at 1.5 times the speed of light.

Matter is different because if someone on the spaceship throws a baseball forward inside the spaceship, the velocity is not observed to be the same from both the aforementioned observers' points of view, as with light.

I can't answer Ima's question either because I don't understand it.

reply to post by Arbitrageur

If you use this definition:

www.websters-online-dictionary.org...

Perpetual motion is a condition in which work is continuously done without an external supply of energy.

In physics, the definition of Work is Force applied along a Distance.

W = F * d

Force is mass times Acceleration

F = m * a

Acceleration is a change in Velocity

a = final Velocity - initial Velocity

Velocity is a directed magnitude, or in other words, a Vector. Velocity, and all vectors, have a direction as well as a size. Since acceleration is defined as a change in Velocity,

Acceleration can be a change in either the direction or the magnitude of a velocity. Or both.

When an electron moves around an atomic nucleus, the electron's direction changes, therefore work is done without input of energy.



BTW why doesn't the electron stick onto the closest proton?

Also By The Way,

Light has always been measured at a constant velocity, which is why space must be curved-- to allow light to change direction without changing velocity.

So would materials that change the direction of light be changing the curvature of space?

reply to post by jiggerj

Good stuff, Semi. What I find interesting is that I think an atom has a neutral center mass, with orbiting electrons that seem more like suns to me. In a living cell, the energy part (the mitochondria) is not in the center. So, why the reverse in the macroverse?

Stuff 'orbiting' around other things is exactly what I meant. The Mitochondria probably wouldn't still be in the biosphere if they hadn't been included into the cellular system.

I have always had a feeling that living matter could have some different,( or additional) quality or energy than regular universal matter. Mitochondria could empower that quality.

On the societal level--does a society need a government like a solar system needs a sun?

I think the economic system should be more like the sun than the government, and actually the economic system is.

Originally posted by Semicollegiate
When an electron moves around an atomic nucleus, the electron's direction changes, therefore work is done without input of energy.

In oversimplified explanations for lower educational institutions, it's understandable how so many get the impression that the electron moves around an atomic nucleus. In fact some people cite the "as above so below" pseudoscientific mantra thinking an electron orbits a nucleus similar to the way planets orbit the sun.

Our best understanding of electron behavior as explained better in higher institutions of learning is that electrons do NOT orbit the nucleus. So while it's a very common myth, it's a myth, according to scientists who study electrons.

Moreover, even in circular orbits, you are incorrect in assuming that work is done:

Work (physics)

the centripetal force exerted inwards by a string on a ball in uniform circular motion sideways constrains the ball to circular motion restricting its movement away from the center of the circle. This force does zero work because it is perpendicular to the velocity of the ball.

So even if the mythical model of the electron orbiting the nucleus was true, it still wouldn't involve work.

Light has always been measured at a constant velocity, which is why space must be curved-- to allow light to change direction without changing velocity.

So would materials that change the direction of light be changing the curvature of space?

Did you read my earlier post about how glass alters the direction of light? Of course glass has mass and mass warps space-time, however that's an insignificant factor compared to the real reason glass bends light as partially described in my earlier citation of the physicsforums FAQ on that topic.

reply to post by ImaFungi

Is light affected by a magnet or electromagnet? Without touching the beam of light, will a magnet placed next to a beam affect the lights path?

Appearently light is not affected by magnetic or electrical fields. All that I have to go on though, are the assertions of individuals posting on blogs and the lack of any information saying otherwise.

One blogger Lasand recomended reading the papers of Michael Faraday.

Michael Faraday was a working class person who learned about electricity from night lectures in his home town.
He discovered induction. He was a self-taught scientist with no degree.

reply to post by Arbitrageur

In oversimplified explanations for lower educational institutions, it's understandable how so many get the impression that the electron moves around an atomic nucleus. In fact some people cite the "as above so below" pseudoscientific mantra thinking an electron orbits a nucleus similar to the way planets orbit the sun.

Our best understanding of electron behavior as explained better in higher institutions of learning is that electrons do NOT orbit the nucleus. So while it's a very common myth, it's a myth, according to scientists who study electrons.

Moreover, even in circular orbits, you are incorrect in assuming that work is done:

I never said the electron moves in a circular orbit.

The electron changes its position in its shell, and is somehow kept within its shell, or orbital.

The electron is alot like light in that it has a dual nature. It can be treated as a small spherical mass, but sometimes it behaves like a cloud or an amoeba, changing shape and density as it moves.

Originally posted by Arbitrageur

[quote
Did you read my earlier post about how glass alters the direction of light? Of course glass has mass and mass warps space-time, however that's an insignificant factor compared to the real reason glass bends light as partially described in my earlier citation of the physicsforums FAQ on that topic.

Yea but couldnt phonons be curves in space time?

reply to post by Arbitrageur


The first question is; Could it be possible that every point in space is expanding a lot faster then we realize, and the matter assoicated with ourselves and the planet is traveling (yes in all its revolutions and rotations but also) linearly through time (and space...the expanding space) and so the light is just going for a ride with the expanding space when "light is created" which as far to my lacking knowledge would be when an electron is moved "against the grain" compared to its prior material surrounded reference frame. So all the matter is moving as a unit through space, maybe space is always expanding past the matter (in time) and the matter being matter moves slower then space, which is why matter moves slower then light, because light having less mass can be carried by the expanding space(thats the jist of my first question and speculation). Perhaps light is even disturbances in the usually steady flowing spatial expansion. I guess part of the problems of my understanding lie in what makes like travel in a wave, and how it reacts with atoms, how it can travel great distances without being interrupted by atoms.

Yea about the second question, I really just have no clue what light is or how it works.

Originally posted by Semicollegiate
I never said the electron moves in a circular orbit.

You said:

When an electron moves around an atomic nucleus, the electron's direction changes

so talking about movement is thinking of the particle like nature, which is not how physicists see the atomic orbital.

The electron changes its position in its shell, and is somehow kept within its shell, or orbital.

The electron is alot like light in that it has a dual nature. It can be treated as a small spherical mass, but sometimes it behaves like a cloud or an amoeba, changing shape and density as it moves.

The electron atomic orbital is seen as more wavelike, not particle-like, which is why the electron is not said to more around the nucleus as you suggested. It's more like a standing wave. It does behave like a particle when jumping from one orbital to another but that's not really a movement around the nucleus, and what we mean by that is that the energy is quantized. The behavior is still very wave-like before and after the transition.

Originally posted by ImaFungi
The first question is; Could it be possible that every point in space is expanding a lot faster then we realize, and the matter assoicated with ourselves and the planet is traveling (yes in all its revolutions and rotations but also) linearly through time (and space...the expanding space) and so the light is just going for a ride with the expanding space when "light is created"

I still don't understand the question. If I try it sounds like you're asking if the space between the Earth and the sun is expanding at the speed of light and if that's what's carrying the light to the Earth, or something? And I doubt that's what you meant so I assume I'm just not understanding the question.

Originally posted by ImaFungi
Yea but couldnt phonons be curves in space time?

I'm not a solid state physicist so I don't claim to be an expert in phonons, but I don't think so. Look at the path light makes going through a glass pane. It suddenly changes angle in the glass and then changes angle back when it exits. So it certainly doesn't seem "curvy" the way gravitational lensing curves space-time for example.

Originally posted by Arbitrageur

I'm not a solid state physicist so I don't claim to be an expert in phonons, but I don't think so. Look at the path light makes going through a glass pane. It suddenly changes angle in the glass and then changes angle back when it exits. So it certainly doesn't seem "curvy" the way gravitational lensing curves space-time for example.

Ok so a phonon is the quantization of the frequency at which a collection of atoms vibrates at. So this is to say that when light goes through a glass pane it interacts with the vibrating atoms (phonons)? And this interaction causes the light to not just pass through unbotherd? What I mean by curvy, not curvy like a bowling ball or gravity well, but if space-time exists 'everywhere' and can be curved, perhaps (like my theory of magnetism, and the theory of gravity) the atoms vibrate at their frequency, and what phonons are, is the affect these atoms vibrations have on the surrounding space-time. So if space can be curved, or altered, and there is a material thats atoms vibrate hundreads of thousands of times a second, and the surrounding space, closer to the material then further, reacts to this movement and energy, and if you want to say the light that enters this material is not interacting with electrons or nucleolus of atoms, then could it be that the light is interacting with the frequency ripples in the surrounding space of the material?

My other question is a lost cause, I cant explain it well and believe my line of thinking may have been skewed (go figure right). I just wish someone could explain the nature of light. I am familiar with all the simple explanations but I dont think they are adequate, there is still ignorance in those explanation, it lacks much knowing.

reply to post by Arbitrageur

In relativity the behavior of light is fundamentally unlike matter.

What I see is sunlight hitting the side of a house, but not going through the outer walls. What I don't see is a bunch of photons piling up on the ground after hitting the house. So, what's up with that????

reply to post by ImaFungi


Just an aside regarding the supernovae talk.

The explosive nature of a supernova while to many it is easy to explain that "oh it just explodes" is really quite simplified and I am absolutely certain you already know that (not trying to insult anyones intelligence) but exactly what happens in a supernovae is really at the extremes of physics. There are also different 'types' of supernovae that depend upon the star mass, some that do go off and leave nothing at all behind, and some that go off and leave a compact object behind.

Anyway, although the intensity of the EM radiation that is produced by a supernova is extreme (can often outshine their host galaxy) that only represents about 1-5% of the total energy. about 85-90% of the energy emanates from Neutrinos. Based upon simulation and also lab tests (high energy light source fusion experiments) supernova simply fizzle out without neutrinos providing a 'pressure'.

Neutrinos how we know them do not interact that much, but to have as many of them generated during a stellar collapse as in a supernova there is enough of them to provide a kind of gas pressure shock wave. Photons can do this also, it is called Radiation pressure. The bit BUT for this is that Radiation is either transmitted, absorbed or reflected. If Radiation is transmitted, it means that some photons make it through an object and impart zero radiation pressure, while some are absorbed and impart radiation pressure. There is no object that is a perfect transmitter/absorber/reflector...