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Practically, no, not even close.

Phytoremediation is the science word.

Lots of plants do pull "stuff" from the soil and water. They accumulate it in the plant tissue, then you can chop that tree or grass down, burn and collect the ashes to dispose of the hazardous material. It is usually targeted at removing heavy metals from soil or water.

Unfortunately, the Ohio train spill was not heavy metals. Phytoremediation won't work here.

Another reason it won't is the chemical spilled was burned. It resulted in a cloud of ash particles and some hydrochloric acid rain. The acid will have immediately reacted with any soil or substrate to form fairly ordinary salts, such as table salt. It is an acute problem, not a persistant problem.

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Humans evolved as a tribe/group, rather than as individuals. What does this mean for homosexuality? It means that tribes/groups containing homosexual people survived, meaning, it can still be genetic. Aside from that, it's not uncommon for gay/bisexual people to have children of their own, especially today with things like surrogates or sperm donors.

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Long answer is long but here's a way to think about it that is physically accurate and not oversimplified as far as I know (I took general relativity 15 years ago so things get fuzzy and I could be forgetting a relevant detail or two)

A dark energy dominated (ie accelerating expansion) universe will have negatively curved spacetime at very large scales. The gravitational effect of regular mass (baryonic and dark both) is to generate local positive curvature of spacetime, which causes the geodesics of nearby objects to bend toward the mass aka falling inward. If you have a large amount of mass sprinkled throughout the universe, the positive curvature generated by that mass will partially offset the negative curvature effect caused by dark energy, slowing expansion.

Home experiment.

Hold you hand in front of your face. Open your mouth as wide as possible and breathe on your fingers. Does it feel hot, cold or neutral?

Repeat, but close your mouth as narrow as possible so breathing is a tightly focused flow. Does it feel hot, cold or netural?

Other important considerations. Your internal body temperature is ~37°C, but your outer skin temperature is closer to 20°C.

When standing still you have an insulating layer of air around you. Your body is wanting to push out excess heat to prevent cooking itself. It loses that heat by radiating it, or by convection where some carrier rubs over your skin and carries away "heat". If the air is not moving, you have transferred as much heat away as possible and the air in immediate contact with you is saturated with heat. Example: hiding under the bed covers or wearing clothes.

Wind moving over your skin is transferring heat by convection. It is picking up heat from your body and carrying it away, which makes your outer skin feel cooler.

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Locally, the expansion of the universe still obeys the first law of thermodynamics: considering a fixed proper volume of space, expansion acts to dilute the energy density within that volume, doing work in the process.

The energy to do this "comes from" the expansion, which means it slows down over time in the situation where there are attractive forces (i.e. gravity) associated with the energy density. Conversely the present-day universe has its energy density dominated by dark energy, which behaves as a repulsive force which ads energy to the expansion, accelerating it.

For a rigorous derivation of this behaviour your best bet is to get an introductory cosmology textbook and look into the Friedmann equations.

Space based solar power.

Ideally, you would point it at Earth and sell solar energy. Or point it at a solar panel to convert it to microwave frequency as beam that at a receiver on Earth to sell electricity.

Probably not visible to people. Depends how you build it, but for maximum efficiency you will be using a very tightly focussed beam.

Just like your laser pointer is making light using a LED, you can also have a visible light laser. You can only see the laser pointer side on if it passes through some particular like smoke, that bounce the light towards your eyes.

The deepest mine in the world is AngloGold Ashanti's Mponeng gold mine, near Johannesburg in South Africa.

By 2012, the operating depth had already reached 3.9-km below the surface, and later expansions have resulted in digging below the 4-km mark.

The deepest man-made hole in the world is ~12 km called the Kola superdeep borehole in Russia.

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The expansion of the universe is proportional to t^(2/3) in a matter dominated universe and t^(1/2) in a radiation dominated universe. Both have power less than 1, so the universe is decelerating.

In a dark energy dominated universe, the expansion is proportional to e^t, so it's exponentially growing, and exponentially accelerating.

https://en.m.wikipedia.org/wiki/Friedmann_equations

In the current universe (which is mostly dark energy, but has still a lot of matter), it's slowly accelerating.

Those equations come from general relativity and are harder to understand and follow though.

To understand the principle, it's best to think of the universe from an observer point of view with newtonian gravity.

Yes, though the galaxies that are outside the local group have enough energy not to crash into us even if we don't consider dark energy which will push them away even faster. Without dark energy, they would decelerate relative to us, but still always going away.

Hmm. So if I understand you correctly, you're saying that an object that's moving away from us due to cosmic expansion has a finite kinetic energy (relative to us). So, from our perspective we should "expect" that kinetic energy to be falling, as our own gravity pulls them back in.

And then that galaxy, will also see the exact same thing. From its perspective every other galaxy is fleeing *it*. And if every galaxy sees this, and it just so happens that every trajectory has too little KE, then every galaxy would see the other galaxies crashing down on them.

Is that right?

Magnetic fields in planets/moons is caused by having a rotating, magnetic core, which Ganymede does. The size does not matter.

Wireless charging is a type of inductive charging, which works via an application of Faraday's Law. Essentially, if a magnetic field changes inside of a wire loop, it will induce a current in that loop. So, wireless chargers producing a time varying magnetic field, and the phone has a wire loop, so a current is induced, which is used to charge the battery.

Why isn't is used much outside of small, personal electronics? 1.) it's not super efficient. Only the energy that goes into producing the magnetic field that goes through the loops actually goes into creating power, the rest is wasted. 2.) It produces quite a bit of heat for how much power it makes. Make enough power to power something big, and it's going to get real hot.

The observed speed is always less than c.

The comoving speed is not limited. If you consider ont special relativity, it's equal to gamma*v so as v goes towards c, the comoving speed goes to infinity. Even with general relativity, it's still true that the comoving speed goes to infinity as the observed speed goes to c.

gamma is the Lorentz factor 1/sqrt(1-v2/c2)

>The expansion of the universe is kinetic energy. [...] Also, the observed speed is always less than the speed of light, so everything has a finite energy.

Is that true? I thought that for distant galaxies, the recessional speed was often greater than c, since c is only a local speed limit, and does not apply to space time inflation.

Consider the rapid inflation of the universe, which went from electron-sized to golf-ball sized in 10–35 seconds; applying a naïve speed calculation would yield speed = distance / time = 43 mm / 10^(–35) seconds >>>>>> 3 x 10^(–8) m/s.

This is all to say, I'm mostly questioning whether the perceived recessional velocity can really correspond to kinetic energy.

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What's the relationship between radiation, convection and conduction? Are they all just electrons exchanging energy with photons, where the only difference is whether the photons go directly between the substances or whether the atmosphere is involved? Do they happen in equal amounts whenever something is heated? I understand each phenomenon individually, but not how they fit together. It's not like atoms decide whether to engage in a quantum process or a regular Atomic one, is it? Sorry if my question doesn't make sense.

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The expansion of the universe is kinetic energy. The matter is going farther from you (the observer) at a given observed speed and you can compute an energy for that, that's an accurate measure of the kinetic energy. Father things go faster, so they have more energy. Also, the observed speed is always less than the speed of light, so everything has a finite energy.

All the mass between you and a far object cause a gravitational pull towards you which slows down objects. The mass distribution is approximately spherical, so all the mass that is farther than a object gets its gravitational pull on that object canceled.

Things get more complicated when you consider général relativity, and a constant energy that doesn't get diluted by the expansion (cosmological constant, dark energy or vacuum energy) accelerate the expansion of the universe rather than slowing down.

However, for the effect of ordinary matter, Newtonian gravity works fine to explain why it makes the expansion decelerate. General relativity agrees with it.

All observers see themselves in the center, and agree that galaxies decelerate (if only ordinary matter is involved) which correspond to the deceleration of the expansion. It doesn't need a center in the comoving coordinates (the coordinates in which there's no center and no specific observer) to get the same result.

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