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  • The actual answer is

    1. because the universe had to pick a finite number and it probably doesnt use meters as an internal measurement ruler for scaling so it's an arbitrary large random number to us.
    2. Why did it have to pick a finite number? Because it has finite lifespan and resources for actualization. This forces hard speed limit.
    3. The speed of light has nothing to do with light it's a shitty name that makes understanding its true nature needlessly complex.

    In actuality all massless waves/particles including photons, gravitational waves, and neutrinos will move at the speed of light, because thats as fast as anything massless can go. Its a universal speed limit for any real mass-particle, which is ultimately governed by Planck's constant and the symmetry preservation of Penrose spacetime diagrams. Its the speed of causality a universal framerate limit that tells us the universe flows/computes through discrete microstates with ultimate precision limit bounds.

    • You seem smart.

      Can I ask you a question about the speed of light? We measured it as whatever we measured it recently. As in not 13-14 billion years ago. We also noticed that the expansion on the universe is getting faster.

      Is it possible that the speed of light changed since the big bang? We just assume it's the same but what if light (photons or whatever) started off slower and gradually speed up and got more efficient. Kinda like speed runners in video games. We wouldn't have noticed the changed because we measured it after it got faster. And now with the universe expanding faster, maybe light is getting even more quick.

      I heard the idea on a YT video and I've been thinking about it.

      • What your asking directly stems from two related open ended philosophy-of-science questions. These would be " Are universal constants actually constant?" and "Does the speed of light differ in speed at any point of time in its journey between two points of space in a continuous substrate?"

        The answer to both like all philosophy questions is a long hit on the pot pipe and a "sure man, its possible but remains unlikely/over engineering the problem until we have justification through observing it" however I'll give my two cents.

        "" Are universal constants actually constant?" " it probably depends on the constant. Fundamental math stuff that tie directly into computations logic and uncertainty precision limits like pi are eternal and unchanging. More physics type constants derived from statistical distribution like the cosmological constant might shift around a little especially at quantum precision error scales.

        The speed of light probably is closer to the first one as its ultimately about mathematically derived logical boundaries on how fast any two points universe can interact to quantize a microstate. Its a computational limit and I don't see that changing unless the actual vaccum substrate of spacetime takes a sudden phase shift.

        "Does the speed of light differ in speed at any point of time in its journey between two points of space in a continuous substrate?"

        Veritasium did a good video about this one. The answer is its possible but currently unmeasurable . so if all hypothesis generate the same effective results then the simplest among them (light maintaining a constant speed during both ways of trip) is the most simple computationally efficient hypothesis among them.

      • So... I am not a scientist, just an enthusiast. But my understanding is that the speed of universe expansion doesn't correlate with the speed of light. The speed of light is still constant.

        Instead, the universe expansion rate is measured via something called the "doppler effect". Scientists are able to use telescopes and take a snapshot of the night sky. Stars that tend to be brighter and more blue are closer to us. And stars that tend to be darker and more red are farther away from us. By taking snapshots and comparing it with previous snapshots over a long period of time, we are able to see a difference in color in each star which then shows us which stars are moving closer and which stars are moving further away.

        Thus by measuring the speed at which the doppler effect changes, they can determine an estimate and compare whether the universe is expanding or shrinking and the speed at which it expands or shrinks over time without breaking the cosmic speed limit that is the speed of light.

        Another analogy for the doppler effect is that it's similar to what happens when a train passes by us. But in the case of a train, the doppler effect is with sound. As the train gets closer, the sound gets louder and seems more higher pitched. Then when the train passes us and gets further away, the sound fades away and gets lower pitched. All the while though, the speed of the train is still constant.

        Hope that makes sense. And anybody that knows more than me feel free to correct me. ;-)

      • He’s not

    • Nice description. I enjoyed your argument. Just a small correction from my side, neutrinos aren't massless. They are very, very low mass though, and so naturally move very close to c.

    • Do you really believe that in all of eternity, we happen to be just four and a half billion years in? We are probably on our infinite life, and have infinite more to go. Just completely random lives, no idea where we will end up, nothing persists.

      • Do you really believe that in all of eternity, we happen to be just four and a half billion years in? We are probably on our infinite life, and have infinite more to go. Just completely random lives, no idea where we will end up, nothing persists.

        Yes I do, though must clarify its the earth that is estimated 4.5 billion. the universe itself is currently estimated at 13.8 billion years since big bang.

        There's a difference between the philosophical idea of an eternal process of cosmological rebirth, and the experimentally observed behaviors of the current universe we live in captured with our most powerful instruments and our best mathematical models.

        In the 20th century we built telescopes powerful enough to see into the very distant universe and track the movement of galaxies. Because of this technological achievement we observed some strange things.

        First was that galaxies seemed to be moving further and further away from each other. Not only that, they were moving away at an accelerating pace. This uncovered the idea of cosmological expansion, that over time our universe "spreads out" and creates new space between already distant objects.

        Second, because the speed of light is finite, this creates fundamental limits to how far we can observe (the cosmological horizon) and a crazy cool phenomenon where the further you look into the distant universe the further back in time you look due to the age of the light from the star and the distance it traveled. We can literally see how the universe looked billions of years ago and calculate how far back we are looking.

        If you look back far enough with extremely low frequency radio telescopes you can map out the thermal radiation from when the universe was extremely hot and dense about 380,000 years after the Big Bang. This is called the Cosmic Microwave Background. It shows the universe was in a very condensed high energy state.

        Third, we have concepts such as the second law of thermodynamics that says entropy increases in closed systems. Energy always spreads out and systems tend toward disorder on a global level. We have equations that very accurately describe this distribution.

        With these breakthroughs we had enough data to simulate accurate matter distributions of the current universe, observe and accurately model matter distributions in the distant past, and use that model to find a best prediction of what may happen in the future with what we currently know. All three lines of evidence point to a universe that is roughly 13.8 billion years old with a definite beginning and end state.

        This can still be reconciled with spiritual beliefs if your willing to redefine eternity to something more like an eternal cycle of rebirth with the heat death of one universe bootstrapping the creation of the next iteration. You may enjoy Futuramas bit on it.

      • Username checks out.

      • What's so special with four and a half billion years (or 13.8 billion years, if you measure from the big bang instead of the formation of the Solar system and Earth) that makes it so weird for us to "just happen to be" during that time?

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