Posts by William Rothamel


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1) Message boards : Science (non-SETI) : Speed of light question (Message 1721693)
Posted 1 day ago by Profile William Rothamel
Heat cannot spontaneously flow from a colder location to a hotter location


How do it know ? (LOL)
2) Message boards : Politics : existance of god (Message 1721648)
Posted 1 day ago by Profile William Rothamel
Well it is sort of like Hindu religious mythology.

We are jealous of other religions. In Hindu the gods have other avatars that represent themselves (on earth I guess) so we have our holy ghost to represent our god --others just have prophets.

The Greeks and Romans had dozens of gods in the past . We Christians need saints to represent all of the specialties of the ancient gods. With "enlightenment" and maybe poverty we slim down our religion to a more manageable set of mystics or perhaps we are just lazy.
3) Message boards : Science (non-SETI) : Speed of light question (Message 1721644)
Posted 1 day ago by Profile William Rothamel
More to ponder.

Is an electron a black hole ? (check the Schwarzchild radius.)
Are we moving towards Andromeda or are they moving toward us ? If we are both moving then which is travelling faster--how can you tell.

How does a thermos know whether to keep a liquid hot or to keep it cold. (LOL)
4) Message boards : Science (non-SETI) : Speed of light question (Message 1721643)
Posted 1 day ago by Profile William Rothamel
Well, my son.

The tennis ball and the person travelling near the speed of light will not know that they are moving that fast unless they can establish a reference point. If they were in a closed room with no view of the outside they would think that they are stationary--so will all the equations that govern motion for them. So you must ask: their speed is relative to what frame of reference ?? If we were blind or in a closed box for all we would know our galaxy itself might be moving close to the speed of light.

We here on Earth are spinning at hundreds of miles per hour. We are travelling around the sun at 66,000 miles per hour and we also travel around the galaxy at around 500,000 miles per hour. The galaxy itself moves toward other galaxies at about 750,000 miles per hour. Unless we could look out and establish a reference point we would think that we were stationary and therefore not moving at all. Careful measurements on the speed of light and the force required to accelerate an object would not reveal any of these motions from within our closed room.

Quod Erat Demonstratum
5) Message boards : Science (non-SETI) : Speed of light question (Message 1721284)
Posted 2 days ago by Profile William Rothamel
Well here's a thought that may clarify or muddy up the question. If an object (say a tennis ball) were travelling very near the speed of light relative to an observer on Earth we say that it would take an infinite (or extremely large) amount of energy to accelerate it much further. However, a person traveling along with that object would be able to accelerate it quite easily with a little push.

How do you reconcile theory, observation and reality ??
6) Message boards : Science (non-SETI) : Speed of light question (Message 1720934)
Posted 3 days ago by Profile William Rothamel
Glenn ,my son,--old cow

If the fence was that long the cow could touch it and would not feel a thing .

The wire would have to be so thick it could not be made .

Electicity does not travel though wire well.


Wrong on all counts. Is this getting to be a habit for you? It is of course a thought experiment that sheds light (Pun intended) on the question at hand. It speaks to the question of simultaneity of events and it depends on where the observer is placed in the inertial reference frame. The question of what is actually happening and what appears to be happening is at the heart of this overall question. i.e. does length actually contract or does it just appear to contract--very subtle questions that are not well dealt with by most physics texts and professors.
7) Message boards : Politics : U.S. Presidential issues questionnaire (Message 1719868)
Posted 6 days ago by Profile William Rothamel
Funny: all of the Republicans scored within three points --between 80 and 83 while the two socialists scored 36 and 27 percent. Rick Perry was ahead of Trump by 2 points ??
8) Message boards : Science (non-SETI) : Speed of light question (Message 1719422)
Posted 7 days ago by Profile William Rothamel
You're thinking of the relativistic velocity-addition formula.
That's not needed to come up with the right answer.


Take your pick:

velocity addition
length Contraction
Time dilitation
9) Message boards : Science (non-SETI) : Is the universe understandable? (Message 1719368)
Posted 7 days ago by Profile William Rothamel
Her black hole statements?

Yes this person also published articles in which she denies that black holes exist. They have been roundly criticized by others in the field.
10) Message boards : Science (non-SETI) : Speed of light question (Message 1719361)
Posted 7 days ago by Profile William Rothamel
If that's inaccurate do tell me why.


As I said, velocities do not add arithmetically when the speeds are an appreciable part of the speed of light. Their relative speeds to one another have to be less than the speed of light since nothing can travel faster than the speed of light.

Their relative speeds would probably be about .95 or so of lightspeed in free space.
11) Message boards : Science (non-SETI) : Is the universe understandable? (Message 1719130)
Posted 8 days ago by Profile William Rothamel
This lady is in a "Physics theory group" at UNC.

I presume that her "theories" would have some mathematical underpinnings that would pass the muster of Peer Review.

To state that there is no such thing as a black hole may be equivalent to my saying that there is no such thing as an Electron (which I often do). What we both may mean is that we have created a model --which may be fictitious -- in order to explain and control what we see happening. In the case of electricity the equations seem to work very well in everyday discourse--I am not so sure what math comes out of her black hole statements and whether it can be tested physically or at least for mathematical soundness.
12) Message boards : Science (non-SETI) : Speed of light question (Message 1719119)
Posted 8 days ago by Profile William Rothamel
You seem to intimate greater understanding, but I don't see any


As a teacher of some success I find that guiding the student to uncover the answer is far more effective than if I work the problem for them. I am not sure that they would practice enough to secure profound knowledge--if the student works the problem from authoritative equations and hints then he will be truly informed.

Others have laid out the math on this topic and I find trying to use an equation editor on these boards to be burdensome. Rather than me pasting in the math--I will let those who seek to truly understand this question and it's answer to follow the Google search to these topics.

The full understanding and a definitive, numeric answer will only come from the
mathematical physics involved. You may find summaries of these results. It depends on one's desire for profound knowledge or simply an informed understanding to decide how much time and brainpower to invest in this quest.

Hint: the velocities between these two ships can never exceed the speed of light--that is a fundamental belief in the cosmic speed limit. So does that answer the question or do you want to know why ? You may want to argue and challenge this on the basis of universe expansion constants. (Bait for a new question and go-round ?)

My original comment back a few posts ago was obviously false to test the level of physics maturity out there--much like I might do if I were still teaching Physics.
13) Message boards : Science (non-SETI) : Speed of light question (Message 1719113)
Posted 8 days ago by Profile William Rothamel
Yes: time to come clean on the question. You may not be able to calculate the correct answer if you have not had a graduate course in theoretical physics or at the minimum a very thorough high school advanced placement course in Physics (mechanics of relativity), which I think is unlikely.

The trick here is that velocities do not add arithmetically at speeds that are an appreciable percentage of light. Time, distance, velocity: which do you have to treat in a relativistic fashion to answer the question?

I will leave it to those who want a definitive answer to google this question and try to follow the math. You will also need some good skill in algebra and possibly calculus. Also it is essential for understanding that you are clear about which inertial frame of reference you are referring to (ship A, ship B or Earth). In other words: Where is the observer ?
14) Message boards : Science (non-SETI) : Speed of light question (Message 1718852)
Posted 8 days ago by Profile William Rothamel
By that time the ship at point A will have moved on. at some more years (I'll let you figure it out) they will see the ship as it was some years in the past.
15) Message boards : Science (non-SETI) : Speed of light question (Message 1718522)
Posted 9 days ago by Profile William Rothamel
Try this--I think that it is attributable to Einstein.

Imagine a very very long electric fence with a cow touching it every 100,000 miles or so. If the fence is activated the cows would immediately drop of the fence. Now put an observer at either end of the fence and let one of them throw the switch. One observer would see the cows drop off every second or so and the other would see them all drop off at once. Do you agree ?
16) Message boards : Science (non-SETI) : Speed of light question (Message 1718518)
Posted 9 days ago by Profile William Rothamel
When the light reaches point A the spaceship at that point will be long gone. You do realize that we cannot see a great part of our universe because the light will never reach us. The universe is said to be expanding at faster than the speed of light.

The reason that we can see as much as we can is that we are not moving away at an appreciable part of the speed of light relative to these distant objects.
17) Message boards : Science (non-SETI) : Black Holes part 2 (Message 1718512)
Posted 9 days ago by Profile William Rothamel
who prefers writing books that nobody reads


I too read Roger Penrose. He is really the spokesman for Hawking. When Hawking could still utter sounds Roger would "translate" for him during his lectures. I wonder: has Hawking proposed any theories that have been proven ? Do any of these wormhole, portals, leaking black holes and multi-verse theories have the ability to be falsified via experiment.

As for the information being destroyed---are we back into semantics and Schrodinger's cat type of speculation. If the information is "still there" but cannot be recovered does it still "exist" or has it been "destroyed". If it is there but no human can read it --what is it's state then. Has it been transformed as with energy which truly cannot be created or destroyed only transformed.
18) Message boards : Science (non-SETI) : Speed of light question (Message 1718334)
Posted 9 days ago by Profile William Rothamel
Yes of course it does but an observer on each ship would not perceive this since the measurement of position travels at the speed of light. The light from one ship would never reach the other. An observer on Earth would see each one moving away ay 3/4 light speed.
19) Message boards : Science (non-SETI) : Is the universe understandable? (Message 1718091)
Posted 10 days ago by Profile William Rothamel
There is Physics. There is Meta-Physics and Philosophy as well.

It is important to recognize the differences and to call out the vague and downright silly notions that are interpreted by the layman as great scientific truths.
20) Message boards : Science (non-SETI) : Is the universe understandable? (Message 1718072)
Posted 10 days ago by Profile William Rothamel
Remember that we bring in the universe and our day to day reality through our senses. Our brains are actually modeling reality. In some instances there appears to be an understanding and actual control of many of life's scenarios.

However, as things move to the very small, we are driven to invent models that tend more toward convenient fictions. These allow us to manipulate and control what we are working with---electricity is a good example as is Newtonian Mechanics.

Most of so called "Quantum Mechanics" is also easily understood in terms of the fiction we create to explain it to ourselves. In most cases the fiction is successful (Atom and Hydrogen Bombs, spectroscopy etc.) and allows us to understand and control physical things with our version of reality.

The two slit experiment is no longer a great, mysterious duality. Google it and you can read explanations in field theory that explain what is happening in things that we sort of take for being "true" --such as orthogonal variation and oscillation of both the electrical and magnetic fields.

Quantum Weirdness indicates that we need better models. The world is quite complex and hard to truly understand. I like to think that: as time goes on that we are asymptotically approaching "True Reality" The Gaussian Curve never hits zero but it gets close enough for me and the rest of the world to be useful.


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