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Made in us
Thane of Dol Guldur




If E = M(CxC), then (CxC) must = E/M. If this equation is a truism, does the speed of light dictate the ratio of Energy to Mass, does the ratio of Energy to Mass of dictate the speed of light, both, or neither?

(CxC) = E/M has many different values that can be plugged in and work, but in one of the possibilities, everything = 1

(1x1) = 1/1

Is this is what is meant by the term 'singularity'?
   
Made in us
Myrmidon Officer





NC

"c" is not a variable. It's a constant defining the speed of light in a perfect vacuum.

c ~= 300,000,000 m/s^2

That number cannot increase nor decrease. The speed of light isn't dictated by energy or mass. It's a constant.

http://en.wikipedia.org/wiki/Speed_of_light
   
Made in us
Thane of Dol Guldur




I've read that, but I'm not sure I buy it. Assuming the speed of light is constant and not relative seems to me to be a limited view. Of course I am totally out of my league here.

Maybe its relative to the ratio of mass and energy in the observable Universe.

But maybe in things we can't observe (the innards of black holes) as matter crunches together to its most basic compontents, a threshhold is crossed whereby the ratio of Matter to Energy begins to change, and thereby, according to the equation, the speed of light is reduced and reduced and reduced until it reaches uniformity with matter/energy, and no longer moves or moves so slowly that it will never ever be detected within that threshold (event horizon).

Maybe when it hits pure 1:1:1, then Big Bang.

This message was edited 3 times. Last update was at 2014/08/15 12:23:16


 
   
Made in us
Dwarf High King with New Book of Grudges




United States

 jasper76 wrote:
I've read that, but I'm not sure I buy it. Assuming the speed of light is constant and not relative seems to me to be a limited view. Of course I am totally out of my league here.


Start here if you want to explore that idea further.

Life does not cease to be funny when people die any more than it ceases to be serious when people laugh. 
   
Made in us
Myrmidon Officer





NC

 jasper76 wrote:
I've read that, but I'm not sure I buy it. Assuming the speed of light is constant and not relative seems to me to be a limited view. Of course I am totally out of my league here.
It's the speed of light in a vacuum excluding all other factors. Speed of light isn't always constant. It's just a constant value when given specific parameters with one of the more important ones being a perfect vacuum.

Light has all sorts of weird properties that require a bit of study on their own. Look up the basics of "Special Relativity" to learn more.

Admittedly, I've only gotten my minor in Physics and can't help you much beyond fundamental textbook concepts.

This message was edited 1 time. Last update was at 2014/08/14 21:09:43


 
   
Made in us
Thane of Dol Guldur




I am reading these materials, and I thank you for the links.

Something does not compute. It is said that at the center of a black hole, there is infinite density.

This means no spacetime at all. How can light move if it has absolutely no place to go? How can anything be said to have a speed if there is no spacetime?

Also, density = mass/volume. When density is infinite, what does that say about mass and volume? What divided by what gives you infinity?

Lets pretend it says that mass and volume are both infinitely large. E=Infinity x C2 would then mean energy is also infinite within a black hole, and that the speed of light squared is equal to infinity divided by infinity, and we're back to the number 1.

Lets pretend infinite density means that there is no mass and no volume. That would mean E = 0 x C2....no energy, and the speed of light becomes meaningless because Energy 0/ Mass 0 does not compute on my calculator.

I wish I could go back in time and take a gakload of math and physics classes!
   
Made in us
Deva Functionary




Home

 jasper76 wrote:
Also, density = mass/volume. When density is infinite, what does that say about mass and volume? What divided by what gives you infinity?

E=Infinity x C2
You cannot do math on infinity. You cannot add or multiply or subtract or divide.

Black holes have zero volume. Black holes have mass and spin. Spin can be zero possibly.
   
Made in us
Thane of Dol Guldur




OK, I guess I'm just having trouble wrapping my head around any sort of constant in a system of relativity.

Here's another 'riddle me this'. If light and gravity affect objects at the same speed, which I've read has been confirmed through observation, and we look at a star say 7 light years away, can that star truly be said to appear as it was 7 years ago, or does it actually exist in our present exacty as it appears in the sky. Do we simultaneously exist with that star as it existed 7 years ago? That would also mean that we exist simultaneously with galaxies as they existed 13 billion years ago.

In other words, is existence itself relative to the distance of two objects from eachother?

This message was edited 1 time. Last update was at 2014/08/14 23:34:23


 
   
Made in us
Most Glorious Grey Seer





Everett, WA

 jasper76 wrote:
In other words, is existence itself relative to the distance of two objects from eachother?
No.

What you see in the night sky is an optical illusion of how things were at the moment light left the star(s) hundreds or thousands of years ago. In reality, those stars have moved considerable distances from where they appear to be. You cannot actually see the current reality of the galaxy (or the distant universe) due to the time it takes light to reach you. You need to do some calculus to figure out where things actually are in the galaxy.


 
   
Made in us
Thane of Dol Guldur




But the gravity that is tugging on our planet is not the gravity of that star now. We are being tugged on by its gravity from 7 years ago. I know we can formulate the star's course and evolution and how it should exist in our present hypothetically, but if we only ever interact with the star as it existed 7 years ago, in what sense can we say that we coexist simultaneously with any object other than the star as it existed 7 Year ago? That star could go supernova right now, but the event itself will only meaningfully exist (interaction between us and it in the present moment) 7 years from now.

(accounting of course for changes in relative position)

This message was edited 1 time. Last update was at 2014/08/15 01:45:17


 
   
Made in us
Ragin' Ork Dreadnought




Monarchy of TBD

 jasper76 wrote:
But the gravity that is tugging on our planet is not the gravity of that star now. We are being tugged on by its gravity from 7 years ago. I know we can formulate the star's course and evolution and how it should exist in our present hypothetically, but if we only ever interact with the star as it existed 7 years ago, in what sense can we say that we coexist in simultude with any object other than the star as it existed 7 Year ago? That star could go supernova right now, but the event itself will only meaningfully exist (interaction between us and it in the present moment) 7 years from now.

(accounting of course for changes in relative position)


Did you just ask if a tree falls in the woods and nobody is around to hear it, does it still make a sound?

Yes. Events happen, whether or not we observe them, despite the theories leading ostrich scientist have published.

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Made in us
Thane of Dol Guldur




I guess what I am wondering is that beyond the speed of light horizon, do those objects exist relative to you ? If it is fundamentally impossible for information to pass between you and an object, can you be said to exist simultaneously in spacetime with an object that is completely outside of your own spacetime?

P.S. all these questions have come up after reading a George Gamow book. He may be outdated but I've never heard him called a quack. If anyone's ideas are bad there just my speculations and I'm not claiming any knowledge in the field other than reading books geared for a popular audience (Sagan, Tyson, etc)

This message was edited 3 times. Last update was at 2014/08/15 02:06:24


 
   
Made in gb
Longtime Dakkanaut





 Breotan wrote:
 jasper76 wrote:
In other words, is existence itself relative to the distance of two objects from eachother?
No.

What you see in the night sky is an optical illusion of how things were at the moment light left the star(s) hundreds or thousands of years ago. In reality, those stars have moved considerable distances from where they appear to be. You cannot actually see the current reality of the galaxy (or the distant universe) due to the time it takes light to reach you. You need to do some calculus to figure out where things actually are in the galaxy.



While that is intuitive, it also assumes some kind of mysterious universal time as a constant, but the whole point of relativity is that time isn't constant. The idea of a universal "now" is incompatible with relativity (and in many respects reality) . The illusion is not merely optical, it is relativistic. Any physical experiment you could conduct (for example sending a ship to the star) would show that the star was actually where it appeared to be when the ship left (because of time dilation on the ship it would all fit). So the 'real' position of objects is actually quite a complicated matter, and possibly even a question of philosophy more than science. That is why most astronomers like to talk about objects in terms of red an blue shift, rather than get tangled up in what their 'real' (if there is such a thing) position is. Since light is constant is might actually be more sound to accept the apparent position of stars as their real position, since for all intents and purposes: it is.

This message was edited 3 times. Last update was at 2014/08/15 06:12:05


 
   
 
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