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Very much so! If you're curious about neural circuits, check out the app Neuronify.. it's a simple spiking neuron simulator, you can play around with using neurons with different properties to create circuits with multiple stable states, circuits that generate periodic output sequences, and circuits that do specific things in response to an input.

How about the effects of dark matter? I heard from somewhere that most stars revolve around GC with the same or similar orbital period due to the influence of dark matter leveling the angular momentum drop off and causing further stars to have a greater velocity. Is this at all true? If so how do I integrate this with what you said?

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The CMB is light that was emitted, but not until about 380k years after the big bang. Before that matter was so dense in the universe that any light that was emitted was reabsorbed by other matter. There were also other elementary particles in the early universe ~1 second after the big bang like quarks and electrons. By 3 minutes after the big bang, quarks we're forming neutrons and protons. Around 24k years after the big bang, there was more matter than energy in the universe. At 380k years after the big bang, things had cooled Enough for electrons to get captured by hydrogen and helium nuclei, throwing off photons that we still see some of today, the CMB. The CMB doesn't dominate the energy in the universe. It's about 10 orders of magnitude lower than the average matter/energy density of the universe.

I want to add on to this question - would the answer to the above be different if the black hole had no accretion disk?

I’ve searched before but never found an answer, maybe you know. Could you be close enough to merging black holes to feel/be killed by the gravitational waves without already having been killed by the black hole or its accretion disk?

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The other commenter said it well, but just to add an analogy: if you burn a chunk of coal slowly at low temperatures it will last many hours, but if you crush it up a bit and heat it more you can burn it faster. If you blast it at super high temperatures you can get all of your energy in a single big WHOOSH. The total amount of energy released is the same.

The sun burns really really slowly, and only in a relatively small region at the center where it is hottest. The reactors that people are trying to build are trying to burn up the fuel quickly for a number of reasons, one of which is because it’s hard to keep it burning slowly without it sputtering out (to use the same analogy).

Physics (the particle physics part) is the behavior of elementary particles.

Chemistry is the behavior atoms made of elementary particles interacting with each other via electric charge.

Cell Biology is the behavior of a big stew of hideously complex chemicals in bags of water.

Organismal biology is the behavior of millions of those bags of chemical water all stuck together.

Ecology is the behavior of millions of those organisms interacting across the surface of the earth.

Economics is like ecology, but you are looking at all the intelligent organisms, who are much more behaviorally complex and who occasionally do things like read your economics papers and alter their own behavior in response.

It's no wonder it's complicated!

Hang on, if all motion is relative, why can't I pick an object moving in the direction I would like to travel at 99% of the speed of light, the travel at the speed of light relative to that, thereby traveling at 199% speed of light relative to my starting location.

Is it because the speed of light limit is relative to the 'fabric' of space? But in that case, would it not be possible (at least theoretically) to measure speed as an absolute based off whether it is stationary on space's 'fabic' or not?

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Also, if you did somehow figure it out and published your results, the traders and businessmen would read your papers and alter their behavior based on what you wrote....which would change the underlying behavior of the market and probably make your discovery invalid.

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Radar astronomy is the closest equivalent I'm aware of...you basically send out a radio pulse and get the reflection back. I don't think you could make it work effectively with visible light, the amount of illumination (and therefore energy) you would need would be huge.

Neutron stars have a tremendous amount of mass crunched as densely as imaginable, and all that rotational momentum adds up.

The fastest spinning neutron star has an estimated surface speed of about 0.25c, or 25% the speed of light.

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The last paragraph you wrote is extremely important to note and thank you for stating that, the circuitry is much more interesting haha

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There is no normal procedure for the outbreak of a pandemic like Covid-19. Everything was kind of going crazy.

If you want to take the more charitable view, you could say the Chinese government was desperate to stop the virus from spreading and put a much higher priority on wiping out potential sources of infection (eg, the animals) and preventing spread (by locking down) than in getting researchers moving around to sample those animals before they were killed.

If you were going to be less charitable, you might say the Chinese government maybe didn't want conclusive proof to be found that it's mess of wet markets had, predictably, caused another zoonotic disease outbreak and was quite happy to see all the potential evidence killed off before it could be sampled....especially by any independent outside researchers.

One thing that's worth noting is that while it's academically interesting to know the exact path and intermediate hosts that covid took to get into people, it's actually not that important from a public health perspective. We know the broad strokes pretty well even without having all the intermediate steps perfectly filled in.

Well, yes, but that's not relevant for a very simplistic idea of the motion of a galaxy. A singular reddit comment is not comprehensive and would take far more baseline knowledge to promote that sort of understanding.

For the average person they don't know and don't care about that smaller detail.

• Individual particles reach speeds extremely close to the speed of light, but I guess those don't count as celestial objects
• Streams of plasma ejected as beams by quasars, or as shells of matter ejected by supernova explosions, or plasma spinning around a black hole as part of an accretion disk also move close to the speed of light, but these aren't really objects either.
• Black holes or neutron stars that orbit each other in a pair gradually lose energy, causing the orbit to gradually shrink while speeding up. Just before they hit each other they reach speeds very close to the speed of light. With current technology we can observe these minutes to seconds before merger in gravitational wave detectors like LIGO, when they're at their fastest but most transient. But they will be moving very fast for years before the merger - we just haven't found any at this stage in their life yet. The famous Hulse-Taylor binary is 320 million years away from merger, but is already moving at 0.15% the speed of light and will only speed up from here.
• Stars orbiting supermassive black holes, such as those orbiting the one in the center of the Milky Way, can reach very high speeds. The fastest of these with a robust speed measurement is S14, which reaches 3.83±0.06% of the speed of light.[*] Of course, there could easily be even faster stars orbiting this (or other) supermassive black holes that have not been discovered yet
• Simulations show that collisions between rapidly spinning black holes result in asymmetric emission of gravitational waves. These carry away huge amounts of momentum, and by conservation of momentum, the merged black hole gets a substantial kick in the opposite direction. In the most extreme cases, this may result in the black hole reaching 1.3% the speed of light.
• The fastest known free-flying star, S5-HVS1 according to Wikipedia, moves at 0.59% the speed of light compared to the galaxy.

[*]: The stars S4714 and S175 are nominally faster, at 8±3% and 4.27±0.47% of the speed of light, but given their large uncertainty they are probably slower than S14. S62 with 7.03±0.04% looks like it's the fastest one with a good measurement by a good margin, but this one turned out to be an error (which reminds me that I should get around to updating the wikipedia articles mentioning this star).

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