You are here:

Physics/force fields


Hello there. I came across a webpage by an electrical engineer where he discusses the possibility of sci fi like force shields as seen in movies like star trek and star wars ect.. He says that an invisible wall like effect could be accomplished by using superimposed acoustic standing waves. He says yhe same could be done with electromagnetic waves. He says it is possible that such a barrier might even resist penetration by solid objects like seen in sci fi depictions.
Here is the web page like where he explains it better than me:

Do you think this idea is plausible? Does it have any physical merit?

Thank you.

> Do you think this idea is plausible?
> Does it have any physical merit?

Bill B is an original thinker, but his first few sentences betray an obvious lack of understanding of how science works:
"He was certain that the "barrier" had something to do with the noisy pipes, but he was never again able to reproduce the effect.
I'm repeating this story from memory, so some of the details might be wrong."

Science, in order to properly operate, REQUIRES a process of RIGOROUS record-keeping. This isn't to say that an anecdote, badly remembered, can't lead to some important discovery. But it REMAINS a badly recalled anecdote -- not science -- until results can be properly recorded and analyzed.

Furthermore, the craft of science requires REPRODUCIBILITY. If Scientist A in place A at time A set up Experiment 1 and got result X -- and result X is something that is inconsistent with a present understanding of our Universe -- then Scientist B in place B at time B MUST ALSO get result X if she does Experiment 1. If ALL other scientists fail to get result X when re-doing Experiment 1, then the burden is on Scientist A to explain why. The history of science is filled with two types of events, both of which start with Scientist A getting a result that is inconsistent with accepted science:
1) His results are duplicated around the world, and Scientist A wins the Nobel Prize.
2) His results are never duplicated by anyone, and Scientist A either-
-thanks his colleagues for preventing him from making a fool of himself by making a big deal out of results that are obviously spurious or non-existent.
-is ridiculed for making claims before checking if others about whether the results are REPRODUCIBLE.
I was in a class the day after an example of result (1), and the professor (a colleague of the person who RIGOROUSLY held off any announcement before the work was confirmed) said the events were more important than anything he could say in class, and thus spent the entire hour discussing what had just happened. This reluctance to publicly release unusual results is an example of GOOD science -- and Burton Richter DID win the 1976 Nobel Prize.
And an example of BAD science is
And an example of NON-science is the first sentence of Bill B's discussion, where not even Scientist A is able to reproduce the results at place A at almost time A!

Bill B thus starts with a badly remembered anecdote, with no real evidence that what he wants to analyze EVEN HAPPENED. From THIS he goes to
"a possible explanation suddenly appeared to me: superpose a string of harmonic standing waves"

"A spike-impulse or 'delta function' has an interesting frequency spectrum. It is composed of all possible sine waves of frequencies 1,2,3,4,etc. When a large set of sine wave signals are all added together, they cancel out everwhere except at the zero location (origin) of the graph. There they add up to create a large transient-spike."
This is a bit of a stretch from this mathematical fact:

"If the harmonically related acoustic standing waves in the organ pipe are chosen so as to produce a pressure-maximum at the mouth of the pipe"
You can't do that -- by definition, the harmonics add at the MIDDLE of the pipe
Bill's statement is a bit like saying, "If numbers are chosen so as to make 2 + 2 = 5 "
I won't deny that IN THEORY you could add all the harmonics so as to make a delta function AT THE CENTER of the pipe. But not at the end.

"Just by transmitting the proper sound into the organ pipe, perhaps we would see the system "self organize" and produce the thin "pressure membrane" across the mouth of the pipe"
Yes, PERHAPS. And perhaps we can use organ pipes to change lead into gold.

The entire idea is a badly recalled, unverified, and non-reproduced anecdote; followed by a physical impossibility; and ending with a wave of the hand. Not the best science I've seen.

Fun to think about? Yes. A good start for speculation? Better than most.
Any "physical merit"? Not a bit.


All Answers

Answers by Expert:

Ask Experts




I can help with understanding physics that does not involve eggs. I will NOT help with academic or professional questions, which are NOT limited only to homework. Please do not waste your time by asking a question that comes out of ANY kind of academic, professional, or business matters.


Have been fascinated by physical laws ever since I learned, at age seven, that magnets work under water. My study continued through college and has not ceased even after I retired.

B.A. in Physics (with honors) from University of California at Berkeley.M.A. in Physics (with honors) from University of Texas Austin.

©2017 All rights reserved.