First, no object could be accelerated to that speed. Relativistic effects make that impossible. However, gravity waves move at the speed of light so there is some delay in gravitational effects. I’m not a physicist, but I’m pretty sure that if your sun-sized object shot through the solar system at 99.9999% the speed of light, and passed between the Earth and the Sun, it would take about 4 minutes for the object’s gravity to be felt by either the Earth or the Sun.
Wow, that’s an incredible thought. So “ziiiiiiip” there goes the uberobject. 4 minutes later, all of the budgies on earth are knocked off their perches.
Would that uberobject heat up the earth as it passes? Not sure how that would work, but it seems like a good question 🤣
Again, not a physicist, so here’s a bunch of words that sum up to “maybe.”
With the object moving so fast I’m not sure we’d notice anything much. We would only be in it’s gravitational field for a very short time, but it might be long enough to change Earth’s orbit, someone with better math skills will need to field that one.
As for heating the Earth, again that’s a maybe. Gravity is stronger the closer you are to the center of mass. So the near side of the Earth will feel the pull of the object much more strongly than the further side. That will make the Earth want to stretch towards the object as the near side falls towards the object faster than the far side. It would be very slight, think egg-shaped but not to a noticeable degree, but it could be bad enough.
This is called a tidal effect and would generate some heat if we’re in the gravity well of the object for long enough. It would also cause fault lines to pop all over the globe. The object would shoot by very quickly though at 99.9999c so we might be spared the worst of the effects. Again, someone with better math skills could give a more accurate answer.
FYI tidal effects are why the moons of the gas giants aren’t frozen ice balls. The constant flexing as they orbit their planet generates tremendous amounts of heat.
It’s an interesting question, but a bit vague. Even at room temperature, relatively needs to be considered for the motion of electrons.
You’re probably thinking about bigger stuff though. The short answer is that temperature is unbounded so yes, there is a temp at which it is significant for the motion of all particles. I think inside of stars this can happen, but my knowledge jn that area is pretty limited.
Veritassium has a recent video about some of this that you may find interesting if you haven’t already seen it.
Temperature is a measure of kinetic energy at the molecular/atomic level. That said, the gasses falling into a black hole would likely reach such hypothetical temperatures as they near the event horizon.
Certainly! You can see discrete emission lines from the ionized air molecules, which only occurs because of quantum physics. I realize that’s not what you’re asking though.
I did a quick calculation and for a plasma torch (~27000 Kelvin) and assuming air molecules, the average velocity of the plasma ions would only be like 6000 m/s. That’s 0.001% the speed of light, so you aren’t going to see any relativistic effects.
Gravity at the event horizon is inversely related to the mass of the black hole. So for a supermassive black hole, gravity at the event horizon can be weak. But you still can’t escape because it’s too large.
Imagine light trying to escape the Earth’s gravity. Its path is slightly deviated by the Earth, then it gets far enough away that the Earth has little further effect.
Now suppose at that distance, it still experienced the same gravity. So the trajectory of light is deviated a little more. It keeps moving farther away but gravity barely changes, even at huge distances. Eventually all those little deviations add up and it’s going back where it came from. Light can’t escape. It’s a black hole.
I see what you mean… I think. Let’s see if I can be more specific:
Considering that time slows down for particles moving near lightspeed, I was trying to visualize the universe immediately after the Big Bang, if it being so hot - or energetic, I think I mean to say - made time slow down in the entire, still tiny universe. And what effect this may have possibly had in the outcome we observe today.
Surely time had also only just sprung into being so shortly after the big bang? If “everything” was moving near C, there was no “other” time to be relative to?
Yeah… what are the dynamics of such an extreme moment? How does a moment like that unfold from the perspective of a particle that was there?
Does time “start slow” before reaching the “stable rhythm” we experience today?
The fact that I felt compelled to use quotes twice in the previous sentence betrays the fact that I don’t even know how to ask what I’m trying to ask.
I think these are all excellent questions, but to my limited knowledge they haven’t been answered yet. I think these are all active areas of research in cosmology.
They are fun to wonder about though. If you have a deep interest maybe check out your library or bookstore. Once in a while scientists in these fields will write a book about their work in these areas.
I suspect you may be misunderstanding time dilation. From the perspective of a particle, time always passes by at 1 second per second. If you yourself were to travel at relativistic speeds (relative to, say, Earth) your perspective of time wouldn’t change at all. However, observers on Earth would see your “clock” to tick slower. That is, anything you do would progress more slowly from their perspective. In the very early Universe, a given particle would see most other particles moving at relativistic speeds, and so would see their “clocks” tick slower. These sorts of relativistic effects would influence interactions between particles during collisions, decay rates, etc, but are all things we know how to take into account in our models of the early Universe.
The way I understand it, (which is virtually not at all really!) there is no overall universal time or background clock like a force field of time or “stable rhythm” that everything experiences. But every observer experiences its own time, relative to whatever point of reference is used.
This is where my meager brain fully melts down…
If everything is moving through spacetime, the faster through space, relative to C, the slower you travel through time, the slower through space, the faster through time.
So if every particle is moving away from each other equally at C, from each ones perspective it’s own time is slowed to 0, so now everything is eternally rushing away from everything else with no time passing.
Now my reasoning and vocabulary fail completely tbh,
Veritassium ignores a bunch of stuff in that video and hand-waves it away.
I only hear about his videos from other, better channels that correct his mistakes. He’s dead to me ever since that “faster than light” electricity video where he didn’t once use the word induction and made it sound super mystical. Fuck that guy with a thousand meters of wire.
Here’s the video I saw on it. Anyone watching the Veritassium video should watch this after:
Or better yet, find a different video on the relativistic movement of electrons and electron holes in wires, and how it causes magnetism. I don’t have one handy.
It’s a really bad sign when half of his videos need corrections by other channels. Sure, you could say they’re just riding on his popularity, but the fact that he needs corrections is the problem.
The video you linked summarizes the intent and benefit of Veritasium videos at about the 2:25 mark, stating that they are for a general audience. I agree that Veritasium isn’t perfect, and doesn’t provide complete depth, but they do a good job of creating interest in topics. So they accomplish their goal.
Additionally, the video you linked is wrong about the principles it discusses. The drift and diffusion velocity (group velocity) of electrons and holes is small compared to the speed of light. The relativistic effects discussed are caused by the phase velocity, which will be closer to the speed of light in the medium for even small currents.
Edit: originally, I incorrectly worded the last sentence which implied that the electrons and holes had a phase velocity equal to the speed of light. I hope the statement is more clear now, but I’m happy to provide additional clarification if necessary.
According to this Stack Exchange answer, glass reflects around 4-100% of the UV in sunlight depending on the angle of incidence. So you could probably get a sunburn if the angle is low enough (like if the Sun is almost directly overhead and reflecting off a vertical window).
It really depends on the type of glass some glass transmits UV light and some types reflect UV light. And that is not taking into account the pile of other factors that will affect it.
I'm not sure how much of a difference that would make. That's less than the total cumulative CO2 emissions of China and the US, and it's 1% of 1% of the total mass of the atmosphere
That’s a good point. My number is all of the current biomass (according to Wikipedia), but all the CO2 we’ve produced since the Industrial Revolution was also originally captured by living things. So add all the gas and coal that ever existed on earth to that number.
So a few things that are missing from the current answers. I’m not a geologist, but I have had graduate level paleobotany training, and quite a bit geology coursework. I also worked in paleobotany lab. I do currently do research in biogeochemical cycling, so while I can’t speak to the nature of continent or mountain building, but I can speak to how our planet has changed chemically, and that in many ways, life on earth has already fundamentally altered major components of the biogeochemical processes that result in geologic formations. This is not quite what you asked, but I think a geologist with the right training could weigh in on the back to further the conversation.
So the two processes I would speak to are the formation of bituminous coal , and the formation of limestone, both of which are biological in origin.
Coal as a type of sedimentary rock involves the conversion of dead vegetation in wetlands, when vegetation dies and is submerged in an anoxygenic environment. The basic process is that vegetation grows, dies, and is buried in a low oxygen environment, and eventually turns into coal, which has retained most of the C-C bonds that were originally present in the plant tissue (cellulose). So how important is evolution and life to the formation of coal? Well consider that 90% of coal beds were deposited during the Carboniferous and Permian periods, representing only a brief fractions of earths geological history. Why would this be the case? Well, it was during the Carboniferous that plants evolved lignin, a plant molecule that is not only very resilient to decomposition, but is a structural tissue that allows for the building of large, indeterminate plant parts. This resulted in the first “trees”, which is to say, tall woody plants that could extend a significant distance above the ground because they now had a strong reinforcement polymer they could integrate with cellulose. So all of a sudden, plant life was like “Fuck yeah, trees upgrade unlocked”!
HOWEVER fungi and bacteria had not yet evolved to degrade lignin. Which meant, for around 160 million years, trees were going gangbusters, but no organism had yet evolved to significantly decompose lignin; this resulted in the wood just kind of piling up, and where you had wetland conditions suitable for coal formation, you got coal. So for around 2% of earths history, we had trees, but we didn’t have wood-decomposing fungi. There are other factors at play here like the high oxygen levels from all the plants, and extremely high CO2 levels from ongoing volcanism (I believe the Kamchatka volcanics?), but if not for the evolution of lignin, we would not have coal, and if not for the evolution of wood-decomposing fungus, the formation of coal would not have been curtailed significantly.
I know much less about the formation of limestone, except that there a shit ton more of it than there is coal, but I can speak to it enough to make a few points. Limestone forms mostly in shallow marine environments. Limestone is made from coral and forminfera, basically shell bearing microorganisms. Anything with a shell that lives and then eventually dies in a marine environment can lead to the formation of limestone. Limestone makes up around 25% of the sedimentary rocks on planet earth, which is a shit ton of shells. Its been forming for a very long time.
So a few more considerations. Consider that sedimentary rocks like coal or limestone are much lighter than igneous rocks. Continental crust is like rafts of light rock floating in a sea of heavier oceanic crust. So there is a kind of geological selection process for these lighter rocks to accumulate as continental crust rather than be subducted and then stay subducted. I’m going to stop there because that’s too deep into the geology for me to speculate further on. I can speak to the biogeochemical aspects, but I’m not a geologist.
So from a chemical perspective, the contents of the minerals that make up continental crust have ABSOLUTELY been altered by the trajectory of evolution on planet earth. Now if that would fundamentally alter the outlines of the continents or their movements? That’s beyond what I know about earth history. What I can say is that evolution has had a direct impact on the chemical composition of the atmosphere, and the makeup of major rock and mineral formations that represent a significant portion of the earths crust.
I just want to add all of the organic material that makes soil different from sand. Erosion will turn rocks into small rocks which we call sand. It's plants, fungus and animals that make that into soil. They all work together to digest and excrete what makes up soil. Not to mention that it's fungi that dissolve minerals to make them bioavailable to everything else. So there's lots of ways life changed the surface but I don't know about the base continents
Adding all of that coal and limestone trapped a lot of carbon underground. If that carbon was CO2 instead, the Earth would be much hotter. Perhaps hotter than the boiling point of water and thus there would be no ocean between the continents, like Venus.
The atmosphere sure changed a lot because of life, which might have had its effects on incoming solar radiation? Which might have changed the temperatures of some ocean currents/continental plates? I don’t think it would differ significantly
I think pretty much everything on land would be different: plant induced precipitation, river bank stabilization, carbon sequestration changing the climate and the timing/duration of ice ages and hydrocarbons being ignited by flood volcanism events. All of that would be gone, could even rearrange whole mountain ranges over time by by altering the pressure of glaciers ice on tectonic plates.
I’m no earth doctor, but wouldn’t it be the other way around? Continental drift would affect the lifeforms abilities to survive and adapt, and that in turn would affect the continents surface features, but not the drifting itself?
I’m no expert, but I just scrolled through the Wikipedia article for Eusociality, because I know that’s a really interesting topic in the field you describe, and then picked out all the links to scientists:
And well, descriptive words that get mentioned relatively often: entomologist, biologist and sociobiologist.
Sociobiology is almost a competing theory to sociology, though, in that it tries to explain social behavior with evolution.
The Wikipedia article on sociology does say rather strongly that it is about humans.
My best guess is that while e.g. eusociality would offer a broader range to study, I guess, humanity is just not as interested in the specific details, as they are when studying humans. So, that’s why sociology for animals is presumably not a field of its own, but rather lumped into entomology/biology.
Thanks for the pointers, I’ll have to give’em a look! Eusociality does sound right in line with what I was wondering about, but hadn’t heard of it before!
Sociology is not exclusive to humans. Animals are often studied to provide a simpler view of social interactions, and parallels can be drawn to humans.
It’s a lot easier to get a study approved with animals than with humans.
Also, yeah, humans are animals too, but I’m not writing out “non-human animals” every time.
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