Can any sort of nervous system (vertebrate or cephalopod) run without direct signalling from some sort of brain? Like surely if there are animals without brains but with nerves then nerves can function on their own but our nervous system wouldn’t work without the brain right? And if so is it then possible to have a nervous system run on a brain that has less neurons than the system it self? Surely that’d be impossible?

Yep. But in most scenarios corresponding to human experience the first is reasonably applicable and much easier to understand.

Bar is a unit of pressure, but it is still derived from the Greek root barus, meaning heavy. So we get a few words from the root such as barometer, isobar, baryon (“heavy particle“), barium (due to the high density of barium minerals).

Me too! To me it’s hard to picture at least just vertebrates with more neurons outside the brain then in, I mean how could it run all these systems u mentioned without having more neurons than the actual system needs, or is the reason it is called a neuron because it can function without needing direct signals from the brain?

Perhaps I falsely believed fever is the body ramping up it’s own natural defences and was beneficial within limits.

Sorry, I may have misread something.

New question: what you exactly mean by "compared to itself"? It can't be literally itself in the same state, as it would be the same, all the time. Can't be a chunk of the material, or any material that has the same temperature in its core and surface would be at 0 difference and...incomperable?

Also, using thermometers isn't using an external point if reference in general? Originally nercury's change in volume to tell a completely different material's temperature. Works because energy transfer.

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Body temp is a secondary effect of your immune system doing it's job.

Increased body temperature is related to what is called a cytokine storm, most common in flu virus compared to the 200+ common cold viruses.

Some flu viruses cause your body to sound the emergency alarm too loud and the body overreacts. The fever is unwanted inflammation that can lead to organ failure.

Ah... So if I had two atoms, could I be right half the time? 😂

It is inherent in the definition of temperature that the substance is compared to itself. You cannot have an external reference point for temperature, because then it's not temperature.

My favourite coffee fact: all types of coffee are a laxative, both regular and decaf. However, we don't know what molecules in the coffee are responsible!

Caffeine isn't beneficial or negative in the long term.

• It stimulates the central nervous system.

• It releases free fatty acids from adipose (fatty) tissue.

• It affects the kidneys, increasing urination, which can lead to dehydration.

• Genetic variation for caffeine tolerance has an oversized effect on population studies.

Despite what popular press loves to talk about, any observable effect is minuscule, complicated and multivariable and you only have to wait a week to find a differing result.

For comparison, taking 1/4 of an aspirin tablet a day has been proven to extend the lives of a small group of humans (potential heart attack, age 40-65), but have zero effect on the majority.

> other stimulants like...

All stimulants, caffeine included, increase heart rate (HR) and blood pressure (BP).

Mostly your caffeine intake is low. A bottle of Coke only has 35ish mg of caffeine.

It is a very quick Google to find examples of sensitive people developing acute heart problems due to excessive caffeine intake.

I was an AIDS research scientist in the 80's. We had the lab we worked in without any infectious material in it (did the live virus work in another room). Anyway, one day we had a plumbing issue and the plumber did not want to come into the lab where all of us were working in. I was thinking "dude you think I would be in here if there was a risk of me getting infected?".

Nobody said that we can't have a reference point, just that we have a single atom of an element, as opposed to a macroworld-sized amount to easily determine its phase.

Like if I'm the last person on the world, I can't tell if I'm handsome or if I'm rich, without other people to compare myself. But I know how fast I am, because I don't need other people for a reference system.

BEC is also an emergent, a phase of matter that only exists in aggregate. The key characteristic of a BEC is that multiple atoms can be described as a single quantum mechanical entity.

The second is special case of the first. The statistical mechanics temperature really is the fundamental one.

Water evaporates even below 100° so it's hard to use any single value for measuring a phase.

His point to my understanding is that is kind of the point. There’s probably tons of variables like this for every solid and liquid. And the sole fact they are solid or liquid does not give them said properties or everything would be identical. The point being everything is extremely nuanced and we’ve created these categorizations so we don’t have to define everything as a mathematical equation instead of ‘solid gas liquid’

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Thats my point. Ofc, in a labratory you need a reference to measure the velocity of a single atom. The reference frame obviously can be broken down to other atoms if you want, but that doesnt mean a single atom cant have kinetic energy by itself.

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So if a single atom moves so fast it loses its electron, it isn’t plasma?

You can't establish energy really, only changes or relative amounts to a reference frame.

>what happens if we drop a second atom in the void?

In doing so, you've introduced energy into the system. That atom had to get there somehow, and that takes energy.

>Besides that, temperature itself isnt relative as we have a true zero.

Yes, it is. It's just self-referential. Thermal motion is the motion of atoms in a substance relative to each other. So if all atoms in a substance have zero motion relative to each other, it has a temperature of 0K.

Thank you...