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a reply to: Arbitrageur

If in between 2 galaxies there exists 2 perfect bar magnets each the size of Earth;

And you start with them held very far apart; and gradually bring them closer to one another;

Will they feel the force of each others magnetism or gravity first?

a reply to: ImaFungi

Well, both would automatically feel the gravitational force. It's infinite in range. Whereas magnetic fields have a finite range.

originally posted by: pfishy
a reply to: ImaFungi

Well, both would automatically feel the gravitational force. It's infinite in range. Whereas magnetic fields have a finite range.

Magnetic fields as such don't have a finite range, are dipole fields, fall off with 1/r^3 compared to gravitational, electric fields with their 1/r^2. Theoretically one would feel both the gravitational and the magnetic field at any time.

a reply to: ImaFungi

originally posted by: pfishy
Well, both would automatically feel the gravitational force. It's infinite in range. Whereas magnetic fields have a finite range.

Yes, I think this is more or less the answer, though the magnetic field also has infinite range in theory, for all practical purposes, at large distances you end up with each pole attracting one pole of the other magnet and repelling one pole of the other magnet, so those attractions and repulsions sort of cancel each other out to a large extent. The exact distance where forces resulting from the magnetic field becomes stronger than forces resulting from gravity (if they ever do) can't be calculated without knowing the magnetic field strength which wasn't specified.

originally posted by: moebius
Magnetic fields as such don't have a finite range, are dipole fields, fall off with 1/r^3 compared to gravitational, electric fields with their 1/r^2. Theoretically one would feel both the gravitational and the magnetic field at any time.

You sure about the 1/r^3? This guy says the force falls off as 1/r^4 at large distances:

isaac.exploratorium.edu...

at large distances, the force between these two magnets should fall off proportional to the inverse fourth power of distance. (Where large distance here means a distance large compared to the largest dimension of the magnet.)

As his qualifier "at large distances" implies, I think the relationship varies by distance, and we can infer that at distances which are "not large" that is not the relationship.

If the magnets were hypothesized monopoles, they would actually follow the inverse square relationship like gravity, it's because they are dipoles that they don't.

a reply to: Diablos

and suppose you could couple to the vacuum fluctuations of the electron field instead of the EM field?

originally posted by: moebius

originally posted by: pfishy
a reply to: ImaFungi

Well, both would automatically feel the gravitational force. It's infinite in range. Whereas magnetic fields have a finite range.

Magnetic fields as such don't have a finite range, are dipole fields, fall off with 1/r^3 compared to gravitational, electric fields with their 1/r^2. Theoretically one would feel both the gravitational and the magnetic field at any time.

I stand corrected. Though, I would imagine that the gravitational attraction would be the initial 'contact' that was substantial enough to begin moving the magnets toward each other. Seeing as how an iron meteorite may pass through our planetary magnetic field, and it is not even a discernable factor in any course alterations. Whereas gravity always is.

Of course, as Arbitrageur pointed out, magnetic field strength was never specified. I was assuming a strength comparable to our planet's natural one. Given that the magnets in question are the.'size' of Earth, I think it is a reasonable conclusion. (Assuming here that a 'perfect bar magnet the size of Earth' implies an object with comparable mass.)

originally posted by: pfishy
Of course, as Arbitrageur pointed out, magnetic field strength was never specified. I was assuming a strength comparable to our planet's natural one. Given that the magnets in question are the.'size' of Earth, I think it is a reasonable conclusion. (Assuming here that a 'perfect bar magnet the size of Earth' implies an object with comparable mass.)

I said it was unspecified because saying it's a bar magnet the mass of Earth with a magnetic field strength similar to earth seem to be contradictory claims.

The Earth's magnetic flux density is only about 0.5 Gauss, whereas a small bar magnet has a magnetic flux density of 100 Gauss. So what would be the flux density of a bar magnet with the mass of Earth, 100 Gauss or 0.5 Gauss? There are other variables, like the Earth is only 35% iron and a bar magnet is mostly iron, but the main difference is that bar magnets are as strong as they are because they've been subjected to very strong external magnetic fields. The Earth hasn't been subjected to such a strong external field, and is only generating a much lower flux density field using its internal motion.

It's easy to demonstrate the greater the flux density of a bar magnet compared to Earth's lower flux density by bringing a bar magnet near a compass needle, and seeing that at close range. the bar magnet completely dominates the deflection of the compass needle.

originally posted by: pfishy
Seeing as how an iron meteorite may pass through our planetary magnetic field, and it is not even a discernable factor in any course alterations.

What are you basing that statement on? Is that true and if so, how do you know it?

We can measure very small changes in asteroid trajectories so I wouldn't be too quick to say what is discernable without data.

www.nasa.gov...

"The Yarkovsky force on 1999 RQ36 at its peak, when the asteroid is nearest the sun, is only about a half ounce – about the weight of three grapes on Earth. Meanwhile, the mass of the asteroid is estimated to be about 68 million tons. You need extremely precise measurements over a fairly long time span to see something so slight acting on something so huge."

a reply to: Arbitrageur

Again, you make a.good point. I hadn't considered the composition of the magnets. I just assigned a value similar to that of earth arbitrarily.

a reply to: pfishy

Of course, being a poorly defined hypothetical, I don't see where my assumption is out of the realm of possibility. But, yes, an actual bar magnet, having been created, would likely have a much stronger field strength.

Time in my personal opinion is like distance , a matter of perspective.
Like if I were an alien, and I was looking twards earth from the Vulcan planet, the hypothetical distance would by my start point of observable distance be equal to sues' perspective who was looking from Earth twards vulcan. NOT SO in my humble opinion. Because it's all moving distance changes as well as time. But not uniformally. One question I would have is it possible the two can operate indepently of each other. If so, E but not = MC^2 more rather it would be like this E=MP^2 p=perspective point in the universe. And of course then speed can then be manipulated furthering space exploration beyond our current technology. This is just a thought experiment. But, please add some great critic as to why or why it could never be realized.
Fabled Goddess

a reply to: fabledgoddess

Haven't you slowed down time during your existence here?

originally posted by: fabledgoddess
Time in my personal opinion is like distance , a matter of perspective.
Like if I were an alien, and I was looking twards earth from the Vulcan planet, the hypothetical distance would by my start point of observable distance be equal to sues' perspective who was looking from Earth twards vulcan. NOT SO in my humble opinion. Because it's all moving distance changes as well as time.

This roughly correlates with the theory of relativity by Einstein, that both distance and time are not absolutes, but vary depending on your movement relative to something else. However, to see significant variations in time or distance, one needs to be traveling at a significant fraction of the speed of light.

But not uniformally.

If by uniform you mean linear, correct, the relationship of time and distance compression to velocity is the non-linear function described in this website:

www.1728.org...
It says that if you traveled at half the speed of light, relative to an earth observer, your clock would run 15% slower and distances would seem 15% shorter in your direction of travel. But of you went 90% the speed of light, the effects are more pronounced:

At .9 times the speed of light, the factor becomes 2.294157338705618. Finally, the effects of relativity become significant. What does this factor mean though? If you were in a spaceship traveling at .9 times the speed of light:
1) the ship's mass (and you) would increase by a factor of 2.294
2) the ship (and you) would contract in the direction of travel by 2.294, meaning a 300 foot ship would shrink to 130.77 feet.
3) Perhaps the most interesting change is that 1 year to you would seem to be 2.294 years for someone back on Earth.

You can enter even higher percentages of the speed of light and see how much that would change relative time and distance similarly.

It's an interesting thought experiment, and we do see such effects on particles like muons, but for humans to travel close to the speed of light isn't feasible yet for a number of reasons. With our chemical rockets it would take more mass than the mass of the universe to make a trip to the nearest star in a reasonable time, but even if we solved that problem with more advanced propulsion like project orion, there is still the problem of exposure to radiation at relativistic velocities.

If you're traveling through space at nearly the speed of light, all those particles which were just sitting there not moving much now seem like they are coming at you at nearly the speed of light, and it turns out that's not good for you.

One question I would have is it possible the two can operate indepently of each other.

According to relativity, length contraction occurs relative to your direction of travel, so in that direction lengths would be compressed by the same factor that time is compressed. In the other two dimensions, you don't see length contraction so I guess you could say time compression is independent from length contraction in the y and z axes if you're traveling along the x-axis of a coordinate system.

If you want to read more about relativity here's an introduction:

Introduction to General Relativity

a reply to: Arbitrageur

Thank you so much for clarifying some of the fundamentals. I have always wanted to travel to another planet and have wondered if my perspective would allow for maybe...a more advanced compilation of the "Laws". Or could it change all together? I still have a belief that the speed barrier could be surpassed somehow.


Most individuals who know me, do get impatient with me, when I speak. Hence, slowing time within a 20 mile radius. That is why I look young.

a reply to: fabledgoddess
Through the science of spectroscopy we can tell what other parts of the universe are made of without going there, and while we are looking for any evidence other parts of the universe are different or have different laws from ours, so far we haven't found convincing evidence of that.

Dr. White at NASA heads up their advanced propulsion lab and they research various projects for better propulsion. One of the more speculative ideas is a warp drive. You can't travel through space faster than light but the idea of warp drive is you stretch and compress space in a space-warp bubble around the ship and supposedly that might go faster than light.

I wouldn't hold my breath waiting for the technology to be developed as we don't even know if it's possible, but it's interesting to hear Dr White talking about the research on it:

Dr. Harold "Sonny" White - Eagleworks Laboratories: Advanced Propulsion

NASA Ames Research Director’s Colloquium, August 12, 2014. Human space exploration is currently still in Low Earth Orbit. But what would it eventually take for humans to explore the outer solar system? If the ultimate objective is the stars, then what might that look like? How hard is interstellar flight?

Lol Ames is a sham. Watched 10 min of that video and saw they were still pushing GR, so they aren't going nowhere with warp i'm afraid. Trust me. Ames will turn out to be another BLP. Wait and see. Sonny white, what a joke.

a reply to: Arbitrageur

a reply to: Nochzwei
Admittedly the warp drive technology is very speculative so if someone claims that will probably never work I'm inclined to agree, but I still think it's worth researching. Many of the other technologies his team is researching are far less speculative and have much better chances of success, but you probably didn't watch enough of the video to see those.

General relativity however is not speculative, it's a probably incomplete but still very good theory strongly supported by lots of evidence.

Could my modem sitting abut to my bass speaker cabinet reduce my WiFi?

I've noticed that since I moved my WiFi router next to my speakers I get half the range for the signal than before the move.

Not even sure radio waves would be effected by speaker magnets but anybody wanna take vs stab at the physics behind my reduced range on my wifi? Would a microwave oven also serve to interfere with wifi?

originally posted by: BASSPLYR
Could my modem sitting abut to my bass speaker cabinet reduce my WiFi?

I've noticed that since I moved my WiFi router next to my speakers I get half the range for the signal than before the move.

Not even sure radio waves would be effected by speaker magnets but anybody wanna take vs stab at the physics behind my reduced range on my wifi? Would a microwave oven also serve to interfere with wifi?

Yes you get what's called radio interference. Ever taken a call in your car and hear a weird buzzing over yoir speakers? Here's one running a microwave can cause yoir wifi to drop. Most routers operate at 2.4 Ghz so do microwaves. In fact electronics in general are all within a very narrow band from 800 my to 5 ghz. Well something called radio-frequency ­interference is the result of a device "listening" for one signal at a specific frequency and "hearing" another. So think back to your science class all EM radiation is a wave. These waves are all happening in one room radio frequencies cell phones speakers wifi, microwaves even other electronics like tvs will put off em radiation. Bottom line to get the best signal range you want to separate all these things as much as possible. Move router to diffrent location keep it away from other electronics. Good General Rule for Routers 5 Ft FROM Speakers 15 from microwaves. This will prevent signals from interfering

originally posted by: dragonridr

originally posted by: BASSPLYR
Could my modem sitting abut to my bass speaker cabinet reduce my WiFi?

I've noticed that since I moved my WiFi router next to my speakers I get half the range for the signal than before the move.

Not even sure radio waves would be effected by speaker magnets but anybody wanna take vs stab at the physics behind my reduced range on my wifi? Would a microwave oven also serve to interfere with wifi?

Yes you get what's called radio interference.

From a microwave, maybe - they're in the same frequency range as the wi-fi. Unless it's 5GHz.

From speakers, no. Speakers do not emit RF.

Ever taken a call in your car and hear a weird buzzing over yoir speakers?

You're hearing the transmission bursts from the phone being rectified by semi junctions in the amplifier.

These waves are all happening in one room radio frequencies cell phones speakers wifi, microwaves even other electronics like tvs will put off em radiation.

Speakers are totally passive.