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Some guy in the Ozarks thinks Einstein wasn't very smart...

this charming man

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Thanks to a Fark Submitter, I had the opportunity to readthis.

He even Godwined his own piece.

I am in no way an expert, and I understand that sceince is always evolving. Our understanding of things improves over time, but is this guy saying that E=MC2 is not valid because scientists can alter the velocity of light, or am I not understanding his point.
 
The "c" in Einstein's formula E=mc2 stands for the speed of light, which Einstein said is a constant (approximately 186,000 miles per second in a vacuum). That doesn't make sense.

(1) A few years ago, PBS reported that two Germany scientists had altered the speed of light in a laboratory. The scientific community dismissed their work as bad science: it didn't fit Einstein's equation.

(2) The current issue of Harvard Magazine (July-August 2007), however, reports that Harvard University physicist Lene Vestergaard Hau has slowed light beams down to 15 miles per hour (see, www.seas.harvard.edu/haulab/). She compressed a 1-kilometer light beam to just one thousandth of an inch by cooling the transmission medium to near "absolute zero."
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Someone who does not know that the speed of light varies according to the medium in which it is propagating ought not cast aspersions on Einstein.
(4) Astrophysics says that light can't escape from a black hole in space due to the immense gravitational pull of dense matter at its core. In this case, the speed of light is zero or negative.
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Yeah, just like the speed of an orbiting planet must be zero (or negative!) so that it does not escape the gravity of the sun.
Einstein conducted "thought experiments" (as he called it); his work did not involve physical measurement-it was just speculation.
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Boy am I glad I did not pursue my carreer in theoretical physics. Someone might have thought everything I did was just speculation!
 
this charming man said:
Our understanding of things improves over time, but is this guy saying that E=MC2 is not valid because scientists can alter the velocity of light, or am I not understanding his point.
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OK, I'm no physicist but I'll try to answer this one. The velocity of light depends on the medium it travels through. The absolute speed of light is the speed of light in a vacuum - that is, there is an upper limit. In other words, the author of this piece has no frickin' clue what he's talking about.
 
But, from 1905 until his death in 1955, he made no significant contributions to mathematics or physics.
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Just trivial stuff like General Relativity...
 
So, basically: Einstien sucks because:
1. He had funny hair. This shows that he thought he was better than everyone else.
2. He didn't even come up with his own theory.
3. And his theory, which he didn't come up with, is wrong.
4. We know it's wrong becuase... um.. because he just made it up. There's no supporting evidence - otherwise why would we keep hearing about his "thought experiments"?
5. He basically just sat on his ass after 1905. He didn't do anything worthwhile. General Relativity? Pah! I come up with better stuff before breakfast!
6. Lots of people think he's really cool.
7. Lots of people thought Hitler was cool too.
8. Therefore Einstein is just like Hitler! You don't want to support Hitler, do you? Huh?
 
Fascinating. But I give him credit for at least trying to tackle a different subject other than tubing, fishin’, or the annual ‘Hootin an Hollarin’ festival this September.

I have a picture of Einstein on my desk as I type this, and some people who stop by make note of it, but nobody fawns over his picture. And nobody certainly thinks he was useless after 1905. Einstein was no one-trick pony.
 
danielk said:
OK, I'm no physicist but I'll try to answer this one. The velocity of light depends on the medium it travels through. The absolute speed of light is the speed of light in a vacuum - that is, there is an upper limit. In other words, the author of this piece has no frickin' clue what he's talking about.
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ya that was my limited understanding too...
 
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This is something I've always wondered. When I was taught the history of proving the speed of light, it was always in reference to experiments of bouncing light across a river. I checked on the wiki, and it says a number of different experiments:

http://en.wikipedia.org/wiki/Speed_of_light#Measurement_of_the_speed_of_light

Aren't all of these measurements done in an open Earth atmosphere, hence a medium and resulting in terminal velocity?

And please forgive me if this is a stupid question. It's been -ages- since I studied physics.
 
Baron Samedi said:
Aren't all of these measurements done in an open Earth atmosphere, hence a medium and resulting in terminal velocity?
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Yes, as far as I know light does indeed propagate a tiny bit slower through air. However, the chances of a photon hitting a particle become incredibly small the closer you get to vacuum. From evaluating the data it becomes obvious that the velocity approaches an upper limit. Even through solid objects like glass light is just a tiny bit slower than the theoretical maximum velocity.

I reckon there are probably more air-tight theoretical proofs of the absoluteness of the speed of light out there. But I'm not a physicist. Dear physicists around here: please tell me if I'm saying something dumb and I'll eat my foot. :footinmou

ETA: Please replace all instances of "velocity" with "speed". Also, I was wrong about the glass, the speed difference is considerably more than just "tiny". :footinmou
 
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I don't recommend using the terms velocity and speed interchangably. You might be mistaken for an Ozarkian gadfly.
 
hgc said:
I don't recommend using the terms velocity and speed interchangably. You might be mistaken for an Ozarkian gadfly.
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OK thanks, I just looked up the definitions. So the difference is that velocity includes a direction, whereas speed is simply the absolute value of the velocity vector, right? (Unfortunately in German there's only a single word "Geschwindigkeit" for both. You'd have to say "Geschwindigkeitsvektor" or something in place of velocity.)
 
Baron Samedi said:
This is something I've always wondered. When I was taught the history of proving the speed of light, it was always in reference to experiments of bouncing light across a river. I checked on the wiki, and it says a number of different experiments:

http://en.wikipedia.org/wiki/Speed_of_light#Measurement_of_the_speed_of_light

Aren't all of these measurements done in an open Earth atmosphere, hence a medium and resulting in terminal velocity?

And please forgive me if this is a stupid question. It's been -ages- since I studied physics.
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this is likely true, but the most important finding of various early speed of light measurements is that light travels at the same speed regardless of the relative motion between the earth and its source.

Also the ammount slower that it travels in air is not much.

N=C/V and N for air is 1.000277. Light in say a dimond with a index of refraction of 2.417 would be traveling at under half c.

In the sun it can take a million of years for a photon to get from the core to the surface, while sound does this in hours.
 
danielk said:
OK thanks, I just looked up the definitions. So the difference is that velocity includes a direction, whereas speed is simply the absolute value of the velocity vector, right? (Unfortunately in German there's only a single word "Geschwindigkeit" for both. You'd have to say "Geschwindigkeitsvektor" or something in place of velocity.)
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You've got it. Speed is commonly referred to as the magnitude of the velocity vector.
 
ponderingturtle said:
this is likely true, but the most important finding of various early speed of light measurements is that light travels at the same speed regardless of the relative motion between the earth and its source.
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Right. I think I remember that now, when looking at pulsars at different times of the year (speed of light of the pulsar + speed of the Earth in orbit vs. speed of light of the pulsar - speed of the Earth in orbit). But if it is possible that the atmosphere creates a terminal velocity type effect, then this shouldn't matter. Sort of like a feather being dropped from a 1 meter height vs. a 100 meter height -- it will still land on the ground at the same final speed.

Again, just random stupid thoughts here.
 
Silly stuff actually--shows the person doesn't understand the forumula. the C squared in the formula isn't really the speed of light. It is the conversion factor between energy and mass and just happens to be the speed of light in a vacuum squared. The variable speed of light really doesn't happen to have anything to do with this equation.

glenn

The true formula is a bit bigger too...
 
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