morgsboi

While a gravitational slingshot is a good way to gain some speed, returning to earth after sling-shotting around the moon is going to be quite difficult.

 

I don't know what you mean by irregular orbit, either. Once the object is a bit away from the moon (so earth's gravity is dominant), it will be travelling in something very close to an ellipse. Someone clever may be able to figure out a path that makes two, or even three passes -- gaining energy each time. Unfortunately at some point you're going to either circularize your orbit not able to get near earth again without inputting energy (possibly crashing into the moon), or reach escape velocity and never seeing earth again.

 

Secondly, traveling close to the speed of light won't make you travel through time in the Back to the Future sense, all it will do is make time pass at a different rate, so that when you return to earth you will be younger.

What I mean by irregular orbit is an orbit that is interrupted by a secondary source of motion such as an engine. So it would be controlled and as its so close to Earth it won't take much time to fix any problems.

And according to Prof. Stephen Hawking, approaching the speed of light will make time travel slower, so you won't get younger as that would just be reversing time in a way but you wouldn't age as quickly as people on Earth.

This is a theory based on a theory. The theory it is based on is as you approach the speed of light, you will be traveling in time.

My theory is a way to approach that kind of speed. The way of doing so is to use the gravitational pull of Earth to to speed something up. So if we had a probe or space-ship orbiting around the Earth and the Moon in an irregular orbit, a kind of version like that would be what I call, a catapult orbit.

How this catapult orbit works is increasing the velocity by a certain percentage every full orbit. This happens by as the object in orbit, orbits around the Earth and Moon, it dips down further into the Earth in the stronger gravitational field. It would only dip at a slight angle to avoid it crashing down into the Earth. Now you might be thinking that it would actually take more velocity than gained, but remember its an irregular orbit so it would just simply slide out of the "circular orbit" and carry on, around the Moon and catapulting around the Earth again.

I have taken into consideration, the Moon's orbit and how it won't stay in the same place but the principal still works.

I'm no rocket scientist, so I don't know the mathematical formulas which means I can't prove it works but to help give an idea is a rough idea is a quick drawing I made on paint. (It isn't very good because it was hard to draw)

Red is the orbit of the Moon.

Green is a very rough idea of the irregular orbit. The dip at the left hand side of the Earth, is where the object in orbit slides out of the Earth's gravitational pull.

What do you think?

Crappy little thought........

So Nicolaus Copernicus discovered that Earth rotates in orbit around the Sun in 1543. A year is the time it takes for the Earth to do a full rotate around the Sun.

So how did anyone know about years before then. How could it be a measurement of time before it was discovered?

People might say that they would know by the position of the sun in the sky, but how can there be any accurate way of knowing that?

The laser is transmitting coherent photons. What happens later doesn't affect what comes out of the laser.

But wouldn't it still change the frequency.

A laser is a device that emits light (electromagnetic radiation) through a process of optical amplification based on the stimulated emission of photons. (Wikipedia)

Now a laser produces and emits a beam of light where all waves are in phase with each other and have the same frequency.

If you shine a laser (keeping it still) at a moving object then it changes the frequency of the laser beam.

So if you shine a laser at an angle with half of the beam on the moving object and the other half just continuing further would the brief split-second that the object is moving and part of the laser is on and part of it off, would that change the frequency of some of the waves causing the laser to act differently and not be a laser?

If you don't understand ask me, and if this needs to be moved to speculations (not sure) then please could you do it yourself as I don't know how. Thank you.

The Earth orbits in part because, like you guessed, it has a velocity perpendicular to the pull of the sun.

 

Now where did this initial velocity come from? It has to do with when the Solar System formed. Planetary systems form out of the same clouds that form stars. When nebulas collapse due to gravity, a protostar forms at the center, and then is surrounded by what is known as a "protoplanetary disk". Eventually through a lot of mechanisms like accretion and the removal of the disk, you get small planet-like objects. These protoplanets continue to grow in size as they accumulate more and more matter.

 

Now back to your question. These protoplanets are now spinning because the original gas/dust cloud was spinning, even if ever so slightly. Due to the law of conservation of angular momentum, these bodies spin faster and faster as they contract. And before you know it, you have spinning planets and such.

 

I think this is accurate. I welcome any corrections of my simplification of planetary system formation by the more knowledgeable members.

Thank you. Sounds accurate to me and makes a lot of sense.

<--- fun face [that probably is true or alot of asteroids hit the planets and such sooooooo

Yes, but where do the asteroids get there momentum?

Okay, there probably is a simple answer, but as we know the Earth orbits around the Sun. So, why does it orbit? I know it is partly because it is in the Sun's gravitational field but what gave it the momentum to start orbiting?

When a satellite is launched, it needs some initial momentum to push the satellite around the Earth after it escapes the atmosphere.

So is this proof that anything with an orbit has had some initial momentum at some point in time, proving the big bang?

Dynamic friction even exist on the galactic scale. The gravitational tug of passing planets is much the same as the electrostatic forces between passing atoms. The coherent motion of groups of planets will eventually degrade into the random motion of individual planets.

Source: http://physics.info/friction/

A link to the original source would suffice.

http://worldaerodata.com/forum/read.php?5,493

Some bits, I added.

Not giving credit to the source is the same as claiming that it was your original work.

 

Perhaps you were unaware. That's alright. Now you know.

I thought about that, but it didn't say a name all it said was "future engineer".

Plagiarism is not permitted on SFN. Please cite your sources when you quote text verbatim.

It was only for the help of the topic, and I didn't claim it as my own.

"Thinking outside the box" is all too often shorthand for "I want to ignore the demonstrated laws of physics without fear of contradiction." New proposed physics has implications — some very far-reaching — and it is incumbent on the proposer to deal with those implications. That's how science works. You don't get to ignore what has already been observed to be true, you have to be consistent with it.

 

"Science is organized common sense where many a beautiful theory was killed by an ugly fact." Thomas Henry Huxley

 

Also, questioning why someone is here contributing is no more appropriate than if someone were to put the question to you and imply that your contributions have no value.

 

 

 

No, you haven't slowed down time at all, any more than using snail mail slows down time because email exists. It simply introduces a delay.

What I meant was, observable time in the area where the light is slower.

Okay, lets look at this from a chemistry point of view.

The actual maximum burning temperature of a Jet-A fuel (standard jet fuel type in U.S.) is 980 deg. Celsius. If you refer to the Iron-Iron Carbide phase diagram, the temperature at which steel changes from cementite and pearlite (strong phases of steel) to austenite (significantly less strong) is 702.5 deg. Celsius. Also, if a steel structure is exposed to a temperature just below or at the eutectic (702.5 deg.) for a period of time, martinsite is formed (very weak). All it would take is a few I-beams to lose their structural integrity before the "chain reaction" would start. People say that the heat from burning jet fuel cannot melt steel. It doesn't have to "melt" for it to become ineffective. Also, "very strong type of steel" is the most relative statement ever. The steel used in sky scrapers is a standard carbon steel, not heavily alloyed. In any case, the iron-iron carbide phase diagram describes all carbon steels very accurately. Also, when the buildings actually collapsed, all that potential energy was released into heat and sound, which is true for all destructive reactions. So it is kinda possible that after the buildings fell, the temperature of the rubble reached levels higher than any fire could produce. But.......... very unlikely as the building was designed to take the full force of any plane that hit it, and there were also bombs in the building, so I need to think it through a bit better.

There are too many factors of it and every one has lots of different explanations. I think that it was collateral as there is lots and lots of evidence to show, you just need to have the right kind of mind too understand it.

You need to watch a program called: loose change. Heres a link on youtube: http://www.youtube.com/watch?v=i3MN9382eGY

It's really good and contains tonnes of evidence. Sorry but your not the first to discover.

What does the size of the universe have to do with anything?

This bit: A singularity is thought to be the end of time and space.

learn to read.....

I suppose that's possible. Although my theory is, there is no "end" to the universe. It is a constant. I think the big bang was just an ink spill on the paper which spread, and possibly wasn't the only big bang.

Either that or the universe is expanding with light at a constant speed since the first light source in the universe. So which ever photon is furthest away from the big bang, that is how far the universe has expanded.

They are just my theories (out of my head) of an "edge".

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The path of light (and everything else like planets, comets, etc.) is "bent" in a gravitational field because of the warping of space and the warping of time due to the presence of mass/energy (the source of gravity.) This warping of space and time is called spacetime curvature.

Okay, thankyou

Well, I guess we can't answer "why" to a great extent but there are experiments that prove it. The best bet is that light follows the curves in the fabric of space too. Why this happens isn't answered right now.

Ah, I understand. Do you know the proper name for the curves? For research purposes. Thank you

You seem to be hooking up a bunch of lines and called it ''time''. There is only an imaginary space leg which we call time, that is one more dimension of space which we call time. I am afraid, your diagram is nonesense.

Time travel is possible. Mass slows down time which is still time-travel. Or the 4th dimension folding back on itself is also (although not proved or well studied).

The simple reason can be explained in a simple way.

 

You require energy to leave the earths atsmosphere. This is because gravity is pulling your object (the mass of the earth) from your located origin. What if that mass became so dense that the radial force required to leave your origin became that of the speed of light?

 

Simply, a particle of light cannot escape something when the escape velocity exceeds the speed of light.

So if nothing is faster than light, then why would physics allow a force that pulls stronger than light can travel?

Any ideas yet? And also I know it's not really science, its more of a time traveling movie thing, but it still could be used if time travel were possible.

light may or may not be affected by gravity but it is certainly affected by gravitational time dilation.

 

time stops completely at the event horizon.

You say time stops, I don't quite understand how time itself stops. Otherwise the black hole wouldn't be doing anything within the event horizon.

Light is not matter, it has no mass, it's primary composition is just energy, and energy is another form of matter and vice versa. Both are effected by the fabric of space and they both effect the fabric of space. Light can't escape from a black hole simply because the gravity of a black hole is too powerful, it creates a gravitational well so steep not even light has enough speed to escape it.

 

As far as scientists can tell, nothing comes back from the event horizon except perhaps whatever the result is of black hole evaporation. Once light passes the event horizon, it doesn't come out. Black holes don't emit optical photons, so they are the color of black.

But how can even the most extreme gravity affect something that has no mass?

And according to Professor Stephen Hawking, even a black hole is not truly black so it must emit something.

Hi, I'm looking for a website that shows my strongest points of physics so I can pursue them further. I'm 14 and a bit of an all-rounder. And I'm above GCSE level.

Only matter is affected by gravity. And if light is made up of matter, why won't it destroy anything it goes through?

Would this answer be correct:

Black holes warp space-time so much that any particle that crosses the event horizon finds that simply moving forward in time also moves it toward the singularity at the center of the black hole. The only way anything could escape the black hole would be if it could travel faster than light. You can view an event horizon as being defined to be the boundary between an escape velocity that is lower than c and an escape velocity that has to be greater than c.

Another question that I can't answer is: Would light bounce between the event horizon and the mass? Because Professor Stephen Hawking says that not even a black hole is truly black.

So even in the slightest, light should reflect off the black hole but only to get sucked in again as it can't escape the event horizon.