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Comment Re:Does this mean hydrogen is magnetic at extremel (Score 5, Informative) 16

At high enough temperatures, essentially anything can be magnetic, because they become plasma.
Plasmas allow for electrons to flow freely instead of being tightly bound to atoms.
Once you start moving electrons around, you have an electric current, and if that current's location or strength changes, it will have an associated magnetic field.
It's really tricky to fully model magnetic fields in the sun, because plasmas can be redirected by magnetic fields and they also generate them.

Comment Models and measurements (Score 1) 59

One major issue with astronomy is that the only thing we can measure is light.
Turning that light into distance directly can only be done using parallax which only works for a few dozen light-years on very large objects.
Once you go beyond those objects, everything else relies on converting the received light into a distance via assumptions and some kind of model.
Some of the assumptions seem trivial, like the physics in space are the same as the physics on Earth.
But the idea that space is essentially the same everywhere in all directions, is a nice idea but there could easily by something "very different" beyond our visibility horizon.
When I was doing my astrophysics masters, I found that observational measurements of distances and theoretical measurements were often very different.

It's fine to hypothesize about what would be required to make the "measurements" fit the models and call those things dark matter and dark energy. If those hypotheses are used to place bounds on things. But, so far, there doesn't seem to be much progress in determining how to turn those "dark" things into something testable.
It's like throwing God into the mix. Sure, it "solves" the problem, but without having specific properties/attributes, it doesn't add to our predictive capabilities.

Perhaps it's a "me" problem, but I think the fact that the universe exists means that it must follow fairly simple "rules". The standard model of particle physics is not what I would call "simple", nor is adding more and more terms to describe gravitational interactions. It seems unlikely that 4th order differential equations are being solved at Planck timescales throughout the universe, even if it knows what the initial conditions are/were.
If time and space are linked, and there is no global time, what does it mean to talk about the past of the entire universe?

Perhaps there are large-scale forces that have no measurable terrestrial equivalent?
Perhaps there are interactions between "objects" external to our observable universe?

While the Universe is under no obligation to be comprehensible, it also isn't likely obfuscating itself deliberately.
Although, according to Douglas Adams, once someone figures out the Universe, it will disappear and reappear as something even more inexplicable.

Comment Re: Fruit flies (Score 1) 86

The real problem with trying to "optimize" humanity, from a genetic sense, is that we have no idea which genes will be beneficial to survive some potential species-ending event.
The best solution could come from mutated genes that derive from a serious genetic disease.
Without being able to see the future, I would argue that the more genetic diversity we have available, the more resilient our species will be.

Perhaps if we had a "spare" Earth/Universe and infinite time, we could perform all possible combinations of genes to determine which genome would be ideal for all situations. Maybe we ARE such an experiment.

Comment Benefit of an Objective Pain Measurement (Score 1) 40

I would like an objective way to measure my "pain".
I have damage to my spine that causes bodily responses, such as tear production, but it often doesn't rise to the level of conscious awareness.
This can lead to a level of body disconnection and questions that I ask myself like, "why am I crying?", that I answer with ... I guess I'm in more pain today.
Pain receptors can become exhausted when they continue firing to the same stimulus for an extended period of time.
After that exhaustion period, they will often raise the level of stimulus required to fire the pain signal, but that does not mean that underlying cause has changed.
Perhaps I have nerve inflammation (likely) that results in the release of cortisol or ... something else.
At this point, I find pain to be ... annoying/a distraction.
But it would be more useful for me to feel the pain, so I can, perhaps, avoid the activities that exacerbate the issue.
As it stands, weather changes can lead me to tears, without me being aware that there have been weather changes.
I would like to have a simple way to know that ... something has changed and it's not JUST in my head.

If my pain were ONLY in my mind, then psychological remedies would seem appropriate.

FYI, I generally have a very high tolerance to pain.
I think I had about the same level of tears produced when my fingers were caught in the hinges of a closed garage door.
So, the fact that something I cannot feel induces tears, seems to indicate a level of damage that should be extreme and yet I have no conscious perception of it.

Comment Re:How would this work? (Score 1) 40

All the medication that you mention generally functions to relieve muscle-related pains.
They can also do a decent job of removing your ability to care about a pain that can't be relieved.
Since none of them were very effective, I'm guessing that the pain is nerve-based.
While there are ways to reduce nerve pain, either surgically or medicinally, I would be most concerned about the root cause of the recurring pain.

Is there an infection within the nerves themselves?
Other causes for nerve pain can be spine related, e.g. nerve fiber rubbing against the vertebral bones.
While that doesn't seem likely in your case, weird correlations happen all the time.

The "fun" thing I learned about pain is that it acts as a sobering agent.
It is nearly impossible to get drunk/high while still "attached" to severe pain.
This limits the potential for addiction, provided the dosage does not exceed what is required for pain reduction.
But it doesn't limit the potential for liver damage.
The leading cause of liver damage from the list you provided would be the "acetaminophen/paracetamol" that you might not notice.
It's often listed as APAP and included in many medicines ... at least in the US.

Comment Re:How on earth (Score 2) 82

Since the link is pay-walled, I'll hazard a guess.
Perhaps somebody entered a negative number into a field designed for positive numbers only.
If such a thing happened, it could "wrap around" and count down from the largest value available for that datatype.
Things like that should be accounted for (and prevented) by any developer who has ever had users.

Comment Re:Like the laws of motion (Score 1) 132

If you look into the foundations of mathematics, there are indeed "assumptions".
To make them "feel" better, mathematicians use the term "axiom".
Axioms are statements that must be accepted without proof and they are used as the foundations for proving theorems.
https://en.wikipedia.org/wiki/...

While I was studying for my master's degree in mathematics I heard that the Axiom of Choice can lead to being able to prove some unexpected theorems.

For any mathematical proof, the list of assumptions should be stated.
If mathematics is applied to a physical system, the additional constraints should be stated as well.
Unfortunately, many people ignore, or are completely unaware of, the underlying assumptions.

For example, every proof in physics that I have ever seen assumed that the field of real numbers is applicable to measurements of units such as distance and time. But, if space-time is quantized, it would seem that the field of integers ( or rational numbers) would be more applicable.

Comment Re:This is a waste of money (Score 1) 123

Many of the techniques that are developed for "de-extinction" ARE used to help preserve existing species.
The problem with preservation is that it doesn't generate as much buzz, so they can't get the same level of funding.
It's basically a marketing scheme.
They must show progress with their de-extinction efforts, so they can continue receiving funding.
But the real goal is likely to help preserve biodiversity.

Comment Unstated Optimization Goal (Score 1) 116

There are 2 things that the computations are neglecting: 1) wind and 2) that one may prefer to have 1 side of the body relatively dry.
1) Wind will cause 1 side of the vertical surface to be impacted by more water droplets than the other.
Depending on which way one is facing and the velocity of the wind, it is possible that 1 side remains dry at the expense of the opposite side.
2) I generally don't mind if my back gets wet, because it will often be placed next to the back of a chair/seat minimizing the effects of evaporative cooling. So I generally prefer to keep the front of my body reasonably dry.
By turning my body so that it is facing away from the wind and moving at a speed that is slower than the wind, I can keep the front of my body relatively dry.

All of this assumes the rain is falling relatively slowly, and at a constant rate.
If there is "torrential" rain, the body can become saturated fairly rapidly. After that happens, more droplets won't actually make the body any wetter.

It's always good to state what one is trying to optimize.

Comment Where to watch? (Score 1) 33

Whether or not the collision occurs, there won't any humans or large life forms on Earth's surface in 5 billion years due to the Sun reaching the end of its time as a main sequence star.
If any humans exist in 5+ billion years (even if they don't look like us, if they are 'our' descendants they can still be called human), where should they go to watch the show?
Is there any reason to feel bad if/when a galaxy collision does happen?
Do galaxies feel bad when they merge with other galaxies?

Comment Re: Maybe Halton Arp was right (Score 1) 42

One problem with the hypothesis that the observable universe is contained within a black hole's event horizon is that it would give the universe a preferred direction.
Moving towards the black hole would require less energy than moving away from it.
We observe objects orbiting various other objects, e.g. moons, planets, stars, galaxies, galaxy clusters, and there does not appear to be an overall preferred orbital direction.

A potential workaround would be if the 'black hole' existed in some higher dimensional space.
The entire 3-dimensional space that we observe could potentially exist near its event horizon, and all of the higher dimensions could be compressed down to the 3 that we observe. This might be able to explain accelerating expansion since we would be closer to the singularity now than we were in the past.

These guys look into the concept a little bit: https://www.nature.com/article...

Comment Re:Excellent Illustration (Score 1) 64

The discrepancy is much larger than the "error bars".
The fun thing, for me, is that I did some modeling for my Masters degree and my model didn't match either the other theoretical models, or the models from observation. It was in between them.
This was 20+ years ago, and they still haven't managed to align theory and observation :(

Comment Re:Make Up Shit So You Can Keep Your Overpaid Job (Score 1) 135

I finally understand...

1) Before the flood the world was united under GOD and the continents were together as Pangea.
2) Since everything was closer together, it was easy to get the "right" animals on the arc.
3) Then the flood killed all the "bad people" and the dinosaurs...
4) The flood waters then went away by going UNDER Pangea, lifting it up
5) The animals are released and rapidly go back home
6) Pangea isn't stable with all of that water under it, so it splits apart
7) And this all happened about 4000 years ago?

Yep... it ALL makes sense now.
Anyone who says different is just ignoring science! :p

Comment Re:Ah, winter (Score 2) 135

He said he lived in Texas, not that he was a Texan :)
Plenty of engineers from around the world live in Texas these days.
I live in the ass-backwards state of Alabama, and I generally convert temp. readings based on my presumed audience.
Some of us live in certain shit-hole states, not because of lack of intelligence, or the desire to fuck our relatives, but because we need a decent paying job :)

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