That is true for short periods of time. They will degrade over longer periods of time. However, gravitational mass and inertial mass are not the same thing.
In a weightless environment, water still has the same amount of inertial mass. So does everything else in your body. Water (H2O) in space is just as good for you as water on earth. However, as the article cites, heavy water(HDO, D2O, TDO, THO, T2O ) is bad for you even on earth.
I should add, the equivalence principle states that inertial and gravitational mass are equivalent, but they’re not the same thing.
Wait, what?! How is it not gravity, if it’s indistinguishable?!
Well one is a result of the Higg’s field and binding energy, the other comes from gravity.
Put another way, dropping a block of wood on your toe hurts like hell, so does stubbing your toe on it. Same injury, same result, but differing sources of pain: gravity and inertial mass.
Put another way, if you married an identical twin, and then nailed her sister, she’d be pretty pissed all the same. Don’t cheat on gravity man.
What does linear acceleration have to do with the Higgs field and binding energy?
If you are on a spaceship accelerating at 1g then any experiment you do is indistinguishable from gravity.
However, I hope it is obvious that the reason you are sticking to the floor plates on your spaceship is the result of something other than what makes you stick to the earth (one is acceleration and one is gravity).
Put another way…
Ever go on the barrel ride thing at an amusement park? The one where you stand against the wall of a cylinder and it spins and sticks you to the wall?
What do you think is holding you on the wall? (hint: it is not gravity)
I think this part needs a bit more detail…
Yes. If we removed the mass from your body, any force acting on you would instantly accelerate you to the speed of light, or rather, accelerate parts of your body - which would be inconvenient.
That was my point. How is it not gravity? Serious question.
The real problem would be finding a new dump site after the state of New Jersey sank to the Earth’s core.
Put another way: If the force that holds me to the Earth’s surface results from spacetime curvature (induced by mass), then, does the force that holds me to the walls of the tilt-a-whirl also result from spacetime curvature (induced by motion)?
General relativity follows essentially from two postulates, the general principle of relativity (which says that physics does not depend on the choice of coordinates) and the equivalence principle (you can’t locally tell the difference between acceleration and the effect of a gravitational field). Both are, of course, not proven – they’re postulates, and the other forces depend on postulates of their own – but it would just be a weird universe in which it made a physical difference what numbers we use to coordinatize a manifold, for example. And the understanding of gravity that follows from these assumptions is just as complete (or incomplete) as we have for the other forces, and just as much in account with experiment.
He’s talking about grand unified theories (GUTs). In those, all the microscopic forces follow from a unified principle, but they are ‘broken’ apart into three separate forces in the current state of the universe.
Just a minor point, but in GR, mass is not the (sole) source of gravity, stress-energy is. Stress-energy is a ‘composite’ quantity, whose components are, roughly, the energy density, the energy flux, momentum density and flux, pressure, and shear stress (‘mass’ just being a kind of energy here). So you’d just need to produce the appropriate stress-energy.
Well, we know there’s something that behaves very much like anti-gravity, known as dark energy. This can be, for instance, sourced by a fluid with negative pressure, and there’s no a priori reason such a thing can’t exist.
Spinning your ship is gravity in the same sense as mass is; it leads to a certain stress-energy, which produces a certain space-time curvature. As an example, take the Schwarzschild metric, which describes a spherically symmetric spacetime at the center of which sits a massive object. Spin that object, and you get the Kerr metric, very different from Schwarzschild’s.
It’s gravity, in the sense that it’s locally described the same way as if you were in a gravitational field. Note the locally here: if you go to any finite region, you will be able to perceive tidal effects, which are absent in the case of linear acceleration. However, if you stipulate an infinite massive plane, you’ll also have no tidal forces.
Equivalence holds in an accelerating or spinning spaceship because an observer inside the spaceship sees light beams following the same path they would in an equivalent gravity field. Acceleration moves the floor under the light beam by an amount that equals how much gravity would pull the beam down.
Well, maybe, in the sense of of making a bed while you’re still lying in it.
Or, to ask it another way…
Does my handheld “graviton detector” detect gravitational exchange particles (or lack thereof) when on the tilt-a-whirl that don’t fully account for the force I am feeling?
I think the question to ask does acceleration actually curve space like mass does? Einstein says you can’t tell the difference. But IS there a difference ? Off the top of my head I can’t see how they would be the same…
I’m not sure how you would measure the curvature of space, except by passing light through it.
You use your space curve o meter of course 
But you bring up what I was thinking when I wrote that. That you have to have something moving through space to measure the curvature. And its seem obvious in a handwavy physics way that a curved space and an accellerating elevator with a lightbeam passing through it would LOOK the same effect wise.
Which brings me back to my point. They look the same, but ARE they the same? And I guess if every theory that works says you can’t tell the difference in any way possible then it becomes a moo point.
Do we not already have direct evidence of some form of ant-gravity at work in the universe, which the outward expansion of the galaxies accelerating, contrary to virtually everyone’s expectations?
My pitiful little brains can only think of two reasons for the acceleration. One is some form of anti-gravity. The other is gravity – somehow enough mass beyond the “edge” of the universe pulling things within the universe further out. If this latter thing is the case, then I suppose we have to throw out our entire cosmology.
Wouldn’t it be cool of our universe was surrounded by infinite other universes, only detectable by the gravitational forces they exert on pulling ours apart?
If you are on a spinning space-ship, the gyroscopic motion keeps the center of mass relatively still while throwing your mass against the floor. Your body is in tension against it. With actual gravity, the force draws you down without the axis.
Or is Brain Glutton asking if gravity is in some way a spinning-around? Around what?