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a reply to: dragonridr
That's one possible outcome if the magnetic field isn't strong enough, and I thought about putting that in my answer as one possible outcome, but I decided to assume that we could make a strong enough magnetic field to confine the astronaut so they wouldn't hit the wall.

But the fields required would be ridiculously high, and you also need a field gradient for suspension/levitation. For comparison, look at the field strength in the LHC. I'm not sure what it is after the upgrade but before the upgrade, it was 8.33 Tesla, or about 200,000 times the strength of the Earth's magnetic field, at beam energy of 7 TeV.. It took about 16 Tesla to levitate the frog, and this is at one G, and I'm pretty sure frogs have higher percent water content than the about 60% water content of an adult male (or 55% for adult female).

Let's say 24T might levitate a human from Earth's 1G, since the human has less percent water than the frog levitated by 16T, though this is just an unsourced guesstimate, since I don't think humans will be subjected to such levitation even if a strong enough field could be produced. That's already three times stronger than the 8.33T at the LHC and 600,000 times stronger than Earth's magnetic field.

Next, consider astronauts at takeoff are subjected to maybe 3G, so you're now looking at a magnetic field over a million times stronger than Earth's, and I don't know of humans ever making a continuous magnetic field this powerful. Just look at what it took to make a continuous magnetic field a million times stronger than Earth's magnetic field (the link died so if you want to read the article, you have to click "quote" and copy/paste the whole archive.org link which ATS bbcode linking can't handle):

www.magnet.fsu.edu..." target="_blank" class="postlink">Most powerful continuous man-made magnetic field

World's Most Powerful Magnet Tested Ushers in New Era for Steady High Field Research

TALLAHASSEE, Fla. – A team of researchers from the National High Magnetic Field Laboratory (NHMFL) conducted the first research in continuous magnetic fields of 45 tesla (one million times the Earth's magnetic field) in the new hybrid magnet on December 12. The hybrid magnet represents one of the crown jewels of this national user facility. The NHMFL has achieved its goal from the National Science Foundation of delivering continuous fields of 45 tesla.

The 45 tesla hybrid magnet consists of two behemoth magnets. The total magnet system weighs 34 tons and stands 22 feet tall. An enormous superconducting magnet forms the outside layer and is the largest cable-in-conduit magnet ever built and operated to such high field. It is cooled to within a few degrees of absolute zero with the only operating superfluid helium cryogenic system built for magnet applications in the United States. A very large resistive magnet (electromagnet) sits in the center of the superconducting magnet. The two magnets work in tandem to provide the most intense constant magnetic field on Earth. This new magnetic field strength gives scientists a new scale of magnetic energy to create new states of matter and probe deeper into electronic and magnetic materials than ever before.

This is a "new scale of magnetic energy to create new states of matter", and it's still probably not a strong enough field to levitate a human astronaut against 3 Gs of acceleration. Even the frog might not like seeing what new states of matter are created in his body if you subjected the frog to this.

Also the behemoth magnet system weights 34 tons, while we try to pare down every kilogram possible for space launches because of the expense of launching mass into space, so this is not a space-friendly technology. These are some of the other problems I alluded to in my previous answer.

Even if you could solve all these problems, you've still got the 9G limit which is about where most test pilots in a centrifuge black out because not enough oxygen reaches their brain. We've never come close to making a magnet powerful enough to levitate against this kind of G-force but even if we did, the astronauts would still black out, though I'm not sure if that would be from the G-forces or because the intense magnetic field was creating "new states of matter" in their bodies?

Regarding the new states of matter created at 45T mentioned in the article, it doesn't sound like an experiment I'd like to volunteer for. I'd probably prefer my current state of matter, thank you.


Though the giant magnet is 2 stories tall, the actual test chamber is too small for a human even if you wanted to volunteer to see what 45 Teslas would do to you.

Although the 45 tesla hybrid magnet is a gigantic structure reaching over two stories high, the chamber where the experiments are conducted and the research samples are extremely small. The just completed hybrid experiment had four materials positioned on a single probe with four to ten electrical leads attached to a tiny platform no thicker than a matchbook cover and no bigger in diameter than a #2 pencil.

If gravity is a force it has yet to be identified...
Although it is a part of the Canon of science, which demands proofs, an apple falling, a theorem, some fancy mathematics. And yet where is the graviton?
a reply to: Arbitrageur

a reply to: starswift
You can ask any question about physics here. Sometimes there are answers, sometimes there aren't. We don't know if the hypothesized graviton actually exists, but the way it's hypothesized, we expect it to be nearly impossible to detect, therefore we can't conclude that absence of evidence is evidence of absence in this case.

Considering the accuracy with which we can send probes to Mars or the outer reaches of our solar system which rely heavily on accurate predictions of gravitational force, we obviously have a great understanding of gravitational effects. However, the ultimate mystery of gravity's cause is yet to be solved. If someday we are able to derive the gravitational constant from theory instead of just observation, that should go a long way toward solving the mystery, but we can only measure the observed value so far.

This problem exists not just for the gravitational constant, but with most fundamental constants. We don't know why they have the values they have. While we've learned a lot, there are still plenty of mysteries to keep physicists busy.

originally posted by: starswift
If gravity is a force it has yet to be identified...
Although it is a part of the Canon of science, which demands proofs, an apple falling, a theorem, some fancy mathematics. And yet where is the graviton?
a reply to: Arbitrageur

No gravity is a force by its very definition. An apple falling because of gravity isn't a theorem it's a known observation. Not really sure what you were attempting to say here I presume you question science for not finding a graviton?


One problem we have is its hard to incorporate gravity into our quantum-mechanical models of the other forces and unify them. Electricity and magnetism, the strong, and the weak nuclear forces.Quantum theories of gravity predict the existence of "gravitons" which carry gravity just as photons carry the electromagnetic force.we would love to know "why" matter and energy has gravity, however we know that it does.

Given that as a starting point, we know lots about gravity already but still not as much as we would like to know. Do gravitons exist seems likely since we know everything in the universe started with the big bang. Is it the only possibility well no. Einstein himself didn't think there was a particle involved at all. He saw gravity as a curvature of space time who knows he may be right. I've learned never bet against him In anything.

originally posted by: dragonridr

Yes I've read his papers no I don't agree with him. Do you have a question?

What happens when you subject a too small volume of space to massive amounts of both ac and dc at the same time ?

a reply to: Arbitrageur

You make a very good point. I hadn't even considered the mechanical wear yet. But it makes perfect sense, seeing as how you are increasing the energy density of the fuel mixture. Yet another good reason to just keep saying no.

a reply to: Arbitrageur

I'm always impressed with superfluid helium cryogenics. And notoriously prone to escaping containment vessels as hydrogen is, it's got nothing on superfluid helium. Not only is helium also naturally rather 'leaky', but they're using it in the superfluid state. That makes compressed hydrogen gas look like a jar of pitch in comparison. Here's a nice little video about some of the aspects of it.

Superfluid Helium

a reply to: Choice777

Well, if you would mind clarifying, please, what volume is 'too small', what is it a volume of (air, water, chlorine, vacuum), and what are massive amounts of AC and DC? Is there a certain voltage you had in mind, or did you mean numerous sources of each, or what?
From personal experience, I can tell you that subjecting the relatively small volume of my inner ears to massive amounts of AC/DC is probably one of the contributing factors to the hearing loss I now have.

originally posted by: pfishy
a reply to: Choice777

Well, if you would mind clarifying, please, what volume is 'too small', what is it a volume of (air, water, chlorine, vacuum), and what are massive amounts of AC and DC? Is there a certain voltage you had in mind, or did you mean numerous sources of each, or what?

Agreed more details are needed to answer the question. Even the frequency of the AC matters.

In theory we can't probe anything smaller than a Planck length because to do so would require EM radiation with wavelength so short the energy would be so high as to form a black hole. In practice we can't even approach such a scenario so that theoretical limitation isn't the practical limitation for what's currently "too small".

If the AC and DC means AC and DC current, and we assume it's composed of electrons, the electrons like electrical charges cause them to repel each other so this is going to affect the maximum current densities that can be achieved unless there's a mechanism to overcome the coulomb repulsion between electrons.

Anyway here's an application called a plasma torch. They are usually made to use a fair amount of either AC or DC confined to a small space though I wouldn't call it "too small" as it's the size we want to perform the function needed. They don't use both AC and DC at the same time, though I'm not sure why you would want to when one or the other is sufficient to generate the desired torch temperatures, and the two types of current result in different plasma torch properties. This one uses AC and creates torch temperatures similar to the surface of the sun:

en.wikipedia.org...:Inductively_Coupled_Plasma.jpg

A close-up of a Thermo Jarrel Ash Atomscan 16 inductively coupled argon plasma's torch

So it's way hotter than the Bunsen burner you used in high school chemistry.

As you subject smaller and smaller spaces to the same amount of energy, the energy density will increase, so you'd get a smaller torch radius in an application like this.

From personal experience, I can tell you that subjecting the relatively small volume of my inner ears to massive amounts of AC/DC is probably one of the contributing factors to the hearing loss I now have.

I can see how that kind of AC/DC could cause hearing loss.

a reply to: Arbitrageur

Plasma torches are very handy tools. I've used them many times. As long as what you are cutting can safely be cut by plasma (so that the cutting process doesn't affect a specialized alloy or something), they take about 1/4 of the time of an acetylene/oxygen torch.

I'm saying if anybody has any clue as to what happens when such conditions are meet....actual volume, air, and actuall ac freq and power and dc power are all ....let's just say...way more than that volume of say 1 cm3 can handle....
So let me rephrase..what happens when you saturate space with ac and dc at once.....surprised nobody caught onto it....a very infamous effect happens....come on...

originally posted by: Choice777
I'm saying if anybody has any clue as to what happens when such conditions are meet....actual volume, air, and actuall ac freq and power and dc power are all ....let's just say...way more than that volume of say 1 cm3 can handle....
So let me rephrase..what happens when you saturate space with ac and dc at once.....surprised nobody caught onto it....a very infamous effect happens....come on...

If it's air, you will eventually get an arc. You will also get some tangent loss heating of the air if the AC is of high enough frequency. Depending on the air's dryness and the shape, surface and spacing of your electrodes, you might also get some ozone and free ion formation and a bit of corona.

So if your infamous effect is "an arc", then there you go.

You are not going to have any DC power at all, unless the voltage is high enough to arc or form ions or ozone, since dry air isn't conductive. Thus the current, and with it the DC power, will be zero. With the same caveats, the AC component will pass reactive power, since your air is the dielectric of a capacitor. You will have a very very small real power component tied up with the tangent loss.

originally posted by: Choice777
I'm saying if anybody has any clue as to what happens when such conditions are meet....actual volume, air, and actuall ac freq and power and dc power are all ....let's just say...way more than that volume of say 1 cm3 can handle....
So let me rephrase..what happens when you saturate space with ac and dc at once.....surprised nobody caught onto it....a very infamous effect happens....come on...

Absolutely nothing unless you have somewhere for electrons to travel and travel through. If you took a section of space and tried to apply electricity with nothing being there nothing will hapen. If air is there with sufficient water the current will pass through using the electrons in the water as a conductor. But it needs somewhere to go. In the case of a tesla generator without that path it would be you.

You get the hutchison effect.

a reply to: Choice777
No.
That requires strings and (poor) trick photography.

originally posted by: dragonridr
In the case of a tesla generator without that path it would be you.

Not me personally, I'd wear a conductive suit like this, who's got plenty of AC/DC and arcing from Tesla coil going on:


Giant Tesla Coils-ArcAttack-Playing AC/DC

originally posted by: Choice777
I'm saying if anybody has any clue as to what happens when such conditions are meet....actual volume, air, and actuall ac freq and power and dc power are all ....let's just say...way more than that volume of say 1 cm3 can handle....
So let me rephrase..what happens when you saturate space with ac and dc at once.....surprised nobody caught onto it....a very infamous effect happens....come on...

I have a clue what happens if you specify the conditions but you haven't specified the conditions. First you mention air, then you mention space. There's no air in space, but there's an air 'n Space museum (lame joke from the Simpsons). Air and space are not the same thing, so which is it?

Also AC and DC aren't specific, AC and DC what? Voltage? If you apply high voltages to air (or other gases such as argon in the plasma torch photo above) you get plasma (which is what the arc Bedlam mentioned consists of), if you apply them to space you'll probably get just a high electric field in space but if there's nothing there to form plasma, you'll get no plasma, as dragonridr said.

Lightning is a common form of plasma generated by high voltage in air, which is mostly short duration DC but it also contains transients which are not strictly DC, I wouldn't necessarily call them AC but if you had to refer to the transients as AC or DC, I think you'd have to call them a form of AC.

originally posted by: Choice777
You get the hutchison effect.

There are youtube videos showing clues to the fakery in the hutchison videos. That's not a question about science, it's a question about a charlatan's fakery.

originally posted by: Choice777
You get the hutchison effect.

This is why I think it's good to have a place for people to ask questions.. The guy is a fraud you'd be interested to know he was any the first either. This game of supposedly levitating objects goes back to the early 1900s. It was fake then it's fake now. Short of using an electro magnet you aren't going to make anything defy gravity with electricity.

Now quantum levitation exists and its quite fascinatin. This effect is real and its called the Meissner effect. Basically the magnetic field can't penetrate our object and is forced to travel around it. This causes it to be held In place by the magnetic field. One id the many strange things about superconductivity.

a reply to: dragonridr

Defying gravity means altering inertia and geodesics of light travel, not floating.

Real warp drive should look weird from the outside---local strong gravitational lensing.

a reply to: mbkennel

Defying gravity means altering inertia and geodesics of light travel, not floating.

Nah. Floating means defying gravity.
That other stuff means modifying it.

a reply to: mbkennel

hey mb,

can you explain in more detail the altering geodesic light travel part? sounds intersting.