Do you really think people in 1 million years are going to look back and say, “physicists fully understood the laws of gravity in 2018?”
Yes, actually. I do.
Why 2018 and not 2017?
Why not? They haven’t changed in centuries.
Because it’s likely that the scientific theory of gravitation will be superseded when physicists discover the cause of gravity or whatever. In a million years, there can be a lot of scientific advancement considering we didn’t have any of these things 100 years ago:
- Computers
- Blackberries
- Telephones
- Cell phones
- Microwaves
- Air conditioning
- Snow boards
- Lawn mowers
- Band aids
- Q-tips
- Video Cameras
- DVD Players
- Video games
- CD Player
- iPod
- Software
- Pacemaker
- Space Shuttle
- Airplanes
- Dialysis Machines
- Difibrulators
- Various Vaccines against disease
- Incubators
- Heart Monitor
- Lasers
I think the physicists from a million years in the future would look at our physics like flat Earth pseudoscience. I think there’s no limit to what physicists can accomplish. No matter how much they understand, there will always be more to learn.
In classical mechanics, gravity is a potential energy field. The energy is proportional to height of your center of mass above some reference plane. Up is higher energy, down is lower energy.
I get that in basic physics problems, we usually ignore friction. In a frictionless system, you can have some form of motion go on for ever, as there’s no loss of energy. A spaceship sent off into space, has almost no friction and can go on forever. You can have fun modeling such ideal systems in MS Physics I suppose. Gears with no friction that can just keep turning forever. Perhaps you can come up with some ideal, frictionless dominoes that don’t lose energy and set themselves up, but I’m not sure. In the real world, there is always friction and entropy.
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Nope, and likely we will come to understand it better, but we can probably use some of the discoveries over the past four years from LIGO to help explain. LIGO has proven that gravitational waves exist, which leads us to believe that it might someday find itself in a unified theory that explains gravity along with quantum phenomena.
In the meantime, it might help to think of gravity like a rubber band that you can’t see. It wraps around your center of gravity, pulling on it, and the earth’s center of gravity, pulling on it as well. In fact, you pull the earth’s center of gravity slightly off center, in your direction. If you pull away, the rubber band wants to pull you back.
Except the band is not a band, it’s a wave, and the farther you get from it’s center, it pulls less, not more. On the scale of your dominos though, the rubber band analogy is close enough. Is it possible for the rubber band to pull you toward it, stand you up again, then pull you down again, in perpetuity?
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I totally agree and think that’s an excellent description of gravity.
The way I see it… If there’s a will, then there’s a way. I think it’s technically possible for a machine to work forever, but it’s also nearly infinitely improbable. It’s more likely that the perpetual energy machines of the future would work continually for long periods of time, then stop. From our perspective, it would be perpetual energy if a machine worked for 80 years or something.
Gravity can be used as a source of fuel, so I believe it is harnessable energy. For example:
I think the next step is lengthening the working time of the gravity-powered machine. For example, if the gravity powered lamps’ weight fell at the speed of tree trunk growth (maybe 6" per 30 years), then that would seem like perpetual energy from our perspective.
Here’s a diagram about why I think still objects under the influence of gravity are actually moving. “In physics, motion is a change in position of an object over time.” The force of gravity is moving the cloth from its gravitationally-untouched position.
If gravity is moving still objects, then it must be energy.
Anyways, I’m pretty bad at physics, so I don’t want to argue about the laws of physics anymore. Unless I make any significant improvements to my perpetual energy machine, then I’m calling it quits on this topic.
Don’t feel bad when/if you fail to make improvements. Nobody in the history of mankind has ever had any success in this endeavor. Turns out that the laws of physics are pretty stubborn, and despite our best efforts, we can’t actually get around them. This conundrum makes a perpetual energy machine not only infinitely improbable, they are actually physically impossible.
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When I was a lad, we all knew that the Universe was expanding, but at an ever-decreasing rate. This was due to the gravitational attraction of all of the particles in the Universe pulling them back to the origin of the Big Bang. However, about twenty years ago, I learned that the Universe was actually expanding at an ever-increasing rate. The only explanation would be the presence of something that’s causing matter to repel itself. On large scales it shoves the galaxies apart and on small scales it allows them to coalesce, somehow. This unknown force has been dubbed “dark energy” and, since it apparently exists, could possibly be used to raise (or push) a domino back upright again. This wouldn’t violate the Conservation of Energy since the additional dark energy is what is actually “fueling” the system.
Of course, it wouldn’t technically be a Perpetual Motion Machine, but a Dark Energy Engine.
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Dark Energy Engine!
Dibs on that band name!
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Even for a corner bar post, I feel like I’m getting pretty far out there…
LOL, just when I thought this thread was going to die down! In all seriousness though, dark energy is just a placeholder in equations that can’t be solved without it. It’s hard to prove either way whether it exists or not. The evidence is that “empty” space is dilating, and beyond that, they have no verifiable explanation. That there is an undetectable energy causing it is one posited explanation.
Maybe you are talking about dark matter vs dark energy here (correct me if you aren’t)? Dark energy is the hypothesis to explain the dilation of space, dark matter is the theory to explain the missing gravity necessary to allow galaxies to form. Slightly firmer footing here, there are not only equations but visible gravitational lensing to give credit to the idea that there is otherwise undetectable matter in the universe that in no way interacts with anything other than it’s ability to affect the known universe in a similar fashion to mass by bending it.
At any rate, I mention all of that for this:
I think you’re probably good at physics, most of us are pretty good at physics at an intuitive level, and even physicists aren’t all that much better at it. Can you usually estimate how to toss a ball to someone, or stop a car before you hit someone else’s…yes? Do you break a glass of water every time you set it down on a table…no? Then your intuitive grasp of physics is pretty good, everyone’s intuition has its gaps. On the other hand, if physicists estimates of dark energy and dark matter are correct, only 5% of the universe is even detectable by existing technology, so who even knows what can be done with the rest of it.
Eventually, if you really felt like it, you could learn the equations to calculate turning mass and gravity into watts and then work on how to get the most efficiency out the potential energy of a weight suspended in the air. One kilogram of mass falling one meter under earth’s gravity is 9.8 joules. 9.8 joules converts to 9.8 watts for 1 second or 1 watt per second for 9.8 seconds. How efficiently you convert the energy into the work you want to be performed, for instance, lighting a lightbulb, is the part that we usually focus on. You can always focus on that 95% of the unknown though.
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gravity does not exist. The force you took to stand the domino’s on their end is the potential energy in the theory
gravity does not exist. The force you took to stand the domino’s on their end is the potential energy in the theory
I was referring to “dark energy” … Wikipedia defines this as: “an unknown form of energy which is hypothesized to permeate all of space, tending to accelerate the expansion of the universe.”
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I see, failed to accurately read what you wrote, you said “allows” as in “does not prevent,” I’m sorry about that.
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This is NOT a perpetual motion solution, but if the “dominos” are pinned to the track, you could set them back up ONCE, or topple them in the reverse direction. How? The last object to fall would have to generate a force of approximately 4X the weight of ALL the dominoes. Have the last object to be toppled attached to a pin that will flip the last domino in the reverse direction. The 4X is a guess, I imagine the friction losses are pretty big when all the dominos to be flipped slide against each other. It is NOT perpetual motion, I am actually a Mechanical Engineer…and I don’t do perpetual motion, the Thermo Police actively enforce the first and second laws, as I understand.
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I came across this short video which provides several examples of perpetual motion machines:
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All those machines are loosing energy and will eventually stop but they are fun to look at.
They are also not useful to get any energy from, as they only store the energy that was required to start them in the first place.
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