Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Why would c be the maximum speed reachable ?
I really don't understand this. I mean, c is the speed the photons move, and i beg to differ, but photons have mass. And they say it's the max any particle can reach, given sufficient energy, right ? Accelerating a grain of sand to c would require a tremendous amount of energy afaik. But are we really sure the photon in the smallest particle in the universe ? can't there be other types of smaller particles that we haven't detected yet but still they move at faster speeds than c. By the way, i already expect everyone to say photons are energy, but can't there be smaller particles than photons made of ... i dunno ... energy or whatever, that can move faster ?
2 Answers
- ?Lv 58 years agoFavorite Answer
You seem to be confused about several things. Here are a few scientific facts that have been proven and settled for almost a hundred years now:
1) Photons do not have mass. If they had mass, they could not travel at speed c. If they had mass, electromagnetics would behave very differently and your computer wouldn't work.
2) Accelerating anything with mass, including a grain, to exactly c would require an infinite amount of energy and is therefore impossible as the entire observable universe does not contain an infinite amount of energy.
3) The photon's size has nothing to do with it traveling at c. Smaller objects don't automatically travel at higher speeds.
4) The photon is not smaller than all other particles. All fundamental particles (electrons, quarks, neutrinos, photons, etc.) are the same size, insofar as "size" can be assigned to quantum particles. They are all point particles. That's what it means to be a fundamental particle.
5) Photons travel at c because they have no mass. All particles with no mass travel at speed c in vacuum (such as gluons). In fact, the title "the speed of light" is a historical artifact. A more accurate name for c is "the speed of massless particles".
6) The fact that there is an ultimate speed limit has nothing to do with the size of the photon and in fact has nothing to to with photons at all. You can derive (as my students do in my college class) the nature of the ultimate speed limit without ever referencing light. It is a direct result of the nature of space and time. Light just happens to have no mass and therefore travels at this ultimate speed limit. Whenever you move at some speed relative to a given frame, your time slows down (time dilation) relative to that frame. Because speed is distance over time, time dilation effects your speed. The faster you go, the more your time is dilated and the smaller an incremental addition of speed effects your total speed. This effect blows up (mathematically speaking) right before c, so that it would take an infinite acceleration to reach exactly c. It's a property of spacetime itself and not of light.