Sorry that the OP doesn’t meet your intellectual standard.
The Speed Of Light ??
- Thread starter billt460
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We all ask questions in our ouw way, and we all interpret the written word in our own way.
I do not believe the OP has an axe to grind. I love this post.
I attend the Stanford University KIPAC lectures; the audience is varied; all over the map. I believe every question helps someone else in the room. The only bad question is the one that is not asked.
I’m sure someone will address this but I’ll just comment before reading the rest of the thread.
I think about this a lot because I can’t imagine that the universe has an end, nor that it is infinite! Either choice seems impossible!
The OP is simply asking questions about things in an effort to learn. I appreciate it as I don’t have a solid understanding of these topics but find them fascinating.
It’s unclear where your negativity is coming from here. Everyone in the thread is having a nice discussion, answering questions, asking questions, and discussing space and science in a positive way. You’re seeing things that are simply not there.
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It's not all theory, and maybe a practical example will help you understand the time dilation/speed of light thing is real.
GPS and GLONASS satellites have to account for relativistic effects to keep their clocks synchronized with earth-based ones.
GPS and GLONASS satellites have to account for relativistic effects to keep their clocks synchronized with earth-based ones.
You don’t read other posts before replying, do you?
Even William Shatner has trouble with this kind of stuff.
You’re not alone, Bill. Much of it is counterintuitive. Relativity was extraordinarily controversial when first published in 1905.
It is commonly believed that Einstein won the Nobel prize for relativity, however, at the time, it was unproven, controversial, and counter intuitive. Too controversial for the Nobel committee.
Einstein won the Nobel prize in 1921 for the photoelectric effect which proved the quantum nature of light, also, controversial, but not to the degree of Relativity.
The examples I mentioned previously, like the occultation of Mercury, that proved relativity, proved Einstein was right, but by then relativity was decades old, and Einstein was already world-renowned.
It is commonly believed that Einstein won the Nobel prize for relativity, however, at the time, it was unproven, controversial, and counter intuitive. Too controversial for the Nobel committee.
Einstein won the Nobel prize in 1921 for the photoelectric effect which proved the quantum nature of light, also, controversial, but not to the degree of Relativity.
The examples I mentioned previously, like the occultation of Mercury, that proved relativity, proved Einstein was right, but by then relativity was decades old, and Einstein was already world-renowned.
If you could travel toward a clock, at the speed of light, the clock would not change time for you, but if someone else was standing right beside the clock looking at it, it would appear to operate normally to them.
This is a photon of light captured passing through a 2 liter Coke bottle at a trillion frames per second. I have no idea how they did this, but I am assuming that time is at a complete stand still for the photon, as it is doing this?
A single photon would not be giving off other photons so that you could capture them on film.
That is a laser pulse, so, assuming it’s real, not fake, the laser pulse would have millions of photons in it, some of which are diffracted or reflected throughout the bottle.
What your eye, or in this case, the camera, sees are photons that fall on your retina (or CCD, or film). A single photon is only “visible” if it lands on your retina/detector.
You can’t “see” a single photon as it goes by.
This is a pulse of LOTS of photons. You are only seeing the ones that get bounced off the material towards you.
The speed of light through plastic and coke is going to be very slightly different than light in a vacuum, but, yes, essentially, for photons, which are massless, time is standing still.
That is a laser pulse, so, assuming it’s real, not fake, the laser pulse would have millions of photons in it, some of which are diffracted or reflected throughout the bottle.
What your eye, or in this case, the camera, sees are photons that fall on your retina (or CCD, or film). A single photon is only “visible” if it lands on your retina/detector.
You can’t “see” a single photon as it goes by.
This is a pulse of LOTS of photons. You are only seeing the ones that get bounced off the material towards you.
The speed of light through plastic and coke is going to be very slightly different than light in a vacuum, but, yes, essentially, for photons, which are massless, time is standing still.
Yes cool but not a photon. A pulse
The fact that it is at best a couple of inches long, and traveling at 186,000 MILES PER SECOND make for a pretty amazing shot.
MolaKule
Staff member
@billt460 "I don't know if this guy is right or wrong about this. But how can the speed of light work going away, but not coming back, when both speeds and distances are equal?"
I disagree. I think the OP is saying that from his own perspective, this explanation is counterintuitive to his own experiences, and it is. In our everyday world, we don't move fast enough to experience what Special Relativity (SR) explains.
Learning is all about asking questions, even with a limited knowledge of SR. This doesn't mean the OP has to have a degree in physics.
At about 6:24, Hossenfelder attempts to explain the crux of SR:
https://www.bing.com/videos/rivervi...id=0E4B471DF1AF407E90EFBDB4BDA1E028&FORM=VIRE
I agree. Our experience of the world, our perception, is of a universe governed by Newtonian physics, which is why every single student of physics at some point goes through this reaction of “that doesn’t sound right” when being exposed to special relativity, time dilation, space contraction. Still, it’s established science and the mathematics of it are more accessible than the concept, as shown in this video. You don’t have to have a degree in physics to get into this, but you do have to study some physics.
In this post, folks are addressing the questions respectfully, and suggesting that asking questions and challenging this and that is a good way to learn, and part of scientific inquiry. I have taken a few hits in this for suggesting that the challenge to Brian Cox is ill advised, and that folks need to have a basic understanding of the material to have a meaningful discussion.
wait wait wait.
light speed is constant.....right? is it not our observation of the light through the bottle , what is different?
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In a vacuum, like outer space, light travels at its maximum speed, approximately 299,792,458 meters per second (186,282 miles per second). In our atmosphere, light is slightly slower, around 1.0003 times slower than in a vacuum. This means the speed of light in air is roughly 299,702,547 meters per second.
My understanding is, when we refer to the "speed of light" we are referring to the speed of light in a vacuum. Others can chime in.
My understanding as well.
I think we all accept that Brian Cox knows what he's talking about even if we can't always wrap out brains around it. The very reason that he's famous is that he's good at explaining extraordinary things about how physics and relativity work. I just read today about another Einstein theory being proven with data. https://www.thebrighterside.news/po...-predicted-by-einsteins-theory-of-relativity/
There is also a recent news article challenging Einstein. https://scitechdaily.com/are-we-wrong-about-black-holes-a-radical-theory-challenges-einstein/
For a theory that was published 100+ years ago, this is pretty cool.
Professor Cox travels and lectures all the time. Highly recommended. He will take you on a journey. Simply amazing. I spoke with him in passing for a minute. Did you know he was a rock musician?
