Posted on 04/26/2026 9:45:44 PM PDT by chickenlips
“There is a silence in the night sky that has bothered me for as long as I can remember.”
That line, attributed to Richard Feynman, lands because it gets at a simple, stubborn feeling. The sky looks full. Stars crowd the darkness. It seems reasonable to think someone else should be out there, and close enough to find. Yet the deeper physicists look into the laws that govern the universe, the more that silence starts to seem less like a cosmic riddle and more like a built-in feature of reality.
Human intuition is not much help. It developed for ordinary distances, daily motion, and short-term survival. It did not develop for light years, relativistic speeds, or timescales longer than the history of civilization. As Feynman puts it, “When you take that human intuition and apply it to the scale of the universe, it doesn’t just fail. It snaps.”
That mismatch sits at the center of the story. Five barriers shape the quiet: distance, the speed of light, propulsion, biology, and time. Taken together, they form what Feynman called “absolute walls that prevent civilizations from ever meeting.”
(Excerpt) Read more at yahoo.com ...
absolute walls
BINGO
The same thing was said about man ever flying in the mid-1800s. I suspect that we will find was around what appear to be "absolute walls" at some point in the future.
Actually neither is really true. The “gun type” weapon, the one that was dropped on Hiroshima, they were certain would work and didn’t even need to be tested. Uranium 235 being so scarce and laborious to produce.
Plutonium was different, and the calculations indicated that the “gun type” mechanism would not work. The implosive lens type system was very complicated and needed to be tested, and this was the “fat boy” design tested at Trinity site, and later, dropped on Nagasaki, Japan.
One of the physicists wondered briefly if an atomic explosion might ignite the atmosphere, but this was quickly shut down by more calculations. It does make for a good story.
And I will add, people who speak in absolutes have fragile psyches. Just go to pieces when the paradigm changes. Every single one of them. Without exception. Absolutely.
“ We’ve been broadcasting over a hundred years so anybody within 100 light years would know about us.”
Inverse square law.
L
Your eyeballs will squish and run down your face if you travel faster than 30 mph.
Maybe - but “Alien civilizations have not visited Earth and never will” is a hell of a pronouncement no matter how smart.
“... the additional benefit of not having to put up with people you don’t want near you.”
For some freepers, the entire known universe isn’t big enough for that. Might as well stick with the bunker in Idaho.
No matter how far you run, the cockroaches and tax collectors will always find you.
But the blurry photos and shaky videos...
How does that prove aliens have visited the Earth?
Yep. They’re not coming back. There’s no intelligent life here.
1. Aliens (physical beings originating from another physical location in the observable or unobservable universe) DO NOT EXIST
2. The reason for the “alien” phenomena that we have experienced since the 1940’s, is the continuation of physics bending experimentation and technological development that started with the Manhattan Project and continues to this day.
3. The research is very compartmentalized so that nobody sees the entire picture. Whispers of “aliens” and “recovered” craft are mentioned to the researchers with the demand that “the public CANNOT be made aware of this technology”. The researchers, thinking they are the good guys working on behalf of the good guys, don’t talk about it. If they do become “whistleblowers”, they attribute the tech to aliens. They don’t understand that they are actually working for the people who hold technology that could improve the lives of all humanity but it is being withheld so that the powers that be can maintain control of us.
4. I am open to the idea that there may be other types of beings who have interacted with humans. Maybe they are angels or demons or from another dimension or another time. But they are NOT part of our physical universe for the reasons that Feynman lays out.
Meanwhile, here is a perplexity.ai summary of a similar article:
div>I can do that, but I couldn’t directly fetch the Yahoo page itself. I was able to retrieve a closely matching article on the same topic, which lays out the core objections to interstellar travel: light-speed limits, the rocket equation and fuel mass, antimatter/negative-energy constraints, radiation and micrometeoroids, biological limits, and the long time/communication gap between stars. - compiled by perplexity.aiyahooyoutubethebrighterside
Summary
The article’s central claim is that advanced civilizations still may not visit Earth because interstellar travel runs into hard physical, biological, and logistical barriers, not just engineering challenges. Those barriers are presented as cumulative: even if one hurdle were solved, others remain severe enough to make travel impractical or self-defeating.youtubethebrighterside+1
Factors cited
1. Distance and light-speed limits
The biggest barrier is the sheer distance between stars, combined with the fact that nothing with mass can reach or exceed light speed. The article frames this as a law of physics, not a temporary technology gap.thebrightersideyoutube
2. Infinite energy problem
Because an object with mass cannot be accelerated to light speed without requiring infinite energy, any attempt to reach truly relativistic travel runs into a fundamental wall. That makes the “just go faster” solution impossible in principle, not merely difficult.youtube
3. Rocket equation and fuel mass
The rocket equation creates an exponential problem: fuel has mass, and accelerating that fuel requires more fuel, which adds more mass. As a result, even very advanced ships can become dominated by propellant rather than payload.thebrightersideyoutube
4. Fusion and antimatter limits
The article notes that fusion still leaves a ship burdened by enormous fuel mass, so it does not remove the core problem. Antimatter is described as the best-known high-energy-density option, but producing enough of it would require staggering resources, potentially on the scale of a civilization’s entire output for extremely long periods.yahooyoutubethebrighterside
5. Exotic matter and negative energy
The piece also points to speculative faster-than-light ideas that require exotic matter or negative energy density, which remain theoretical and operationally impractical. In other words, warp-like concepts are not presented as usable solutions with current physics.wikipedia
6. Quantum and relativistic constraints
It cites quantum-theory arguments that some FTL concepts run into instability, dangerous radiation, or bubble-collapse problems. These are treated as additional physical constraints beyond the basic energy issue.wikipedia
7. Radiation exposure
Interstellar space exposes travelers to cosmic rays and other high-energy particles that can damage DNA and electronics. The article stresses that Earth’s atmosphere and magnetic field normally shield life from these hazards.yahooyoutube
8. Micrometeoroids and collision risk
At interstellar velocities, even tiny dust grains become destructive projectiles. That makes shielding a major issue, especially for long-duration travel.youtube
9. Biological limits
Human biology is described as adapted to Earth, not deep space, with problems including radiation damage, long-term health degradation, and the difficulty of cryogenic preservation. The article treats biology as a separate limiting factor, even if propulsion were solved.yahoo
10. Entropy and system lifetime
Even robotic or machine-based travelers face wear, radiation damage, and entropy over long durations. So the problem is not only carrying living passengers, but keeping any complex system functional for centuries or millennia.youtubeyahoo
11. Time, culture, and mission cost
The article argues that even a successful journey could take so long that civilizations might lose interest, resources, or coherence before arrival. It also suggests that the energy and opportunity costs may outweigh the benefits.bbc+2
12. Communication lag
A civilization can transmit signals at light speed, but physical travel is still vastly slower, which creates a huge communication gap between star systems. That makes coordinated interstellar exchange much harder than many popular depictions assume.bbc+1
Bottom line
The article’s logic is that alien civilizations may exist, but the combination of physics, energy, mass, radiation, biology, and timescale makes direct visitation unlikely. It is not saying interstellar travel is absolutely impossible in every imaginable sense, but that the practical barriers are so severe that “why haven’t they come?” may have a very simple answer: because the universe makes it extraordinarily hard.thebrighterside+1youtube
Thank you very much for your clarifications...I did a deeper dive into what you recounted.
Apparently, it was Oppenheimer who had a bet with another scientist and the bet was that the Trinity test would fail. Being that the plutonium implosion type of bomb was just designed and implemented, I would guess that there would be some doubt as to its initial success.
So the statement by Leahy may not have been an example of pompous poorly informed opinion. Or he may have thought that he was opinionating on the failed plutonium “gun-type” weapon.
It was Teller who believed it was possible that the chain reaction after the blast would ignite the atmosphere, and it was Oppenheimer who ran the calculation to show that the atmosphere was not dense enough to support that scenario.
The plutonium bomb was initially tested as a “gun-type” device similar to the uranium bomb. That turned out to be unfeasible. So the scientists had to design the plutonium implosion type. Which was more complicated and had to be tested.
I have read a few books on the Manhattan project but although they are good, they don’t get into the deep, technical details, also, it would seem that my memory failed me a bit here.
Again, thank you for your comments.
Not to mention your hat will blow off and the potholes will rattle your teeth out!
It is likely there are other planets in the universe that harbor life including intelligent life evolving technologies far beyond ours. However, Feynman is right that there are physical barriers that cannot be even be theoretically breached without enormous expenditures of energy.
Perhaps some far off advanced civilization could in theory develop sources of energy and technology beyond our comprehension that might allow interstellar travel. The question then becomes why would such a civilization come here even if they could? If they are that advanced what would we have to offer? The stuff of science fiction is either conquest or some benevolence that brings alien civilizations here. Conquest is pretty meaningless as what is to be gained by subduing the earth and its inhabitants? If a civilization is so advanced as to accomplish interstellar travel there are no resources here they would somehow need or want whether it be humans as slaves or food, minerals or even water. The benevolence idea is equally far fetched. While we have observed chimpanzees engaging in what could be seen as war we see no need to actively stop their aggression let alone to supply them with cellphones or nuclear reactors to improve their lives. Interstellar traveling aliens, despite our most grandiose ideas of altruism, would likely have no more interest in improving things for us than we would stopping a chimpanzee war.
Expending the energy needed to travel interstellar distances also rules out the Star Trek ideal … to boldly go where no alien has gone before. It is not worth the effort simply to sightsee.
What of the UFOs a.k.a, UAPs or of the stories of Roswell etc.? Are they the stuff of interstellar aliens visiting our planet? … likely not. Could they be cutting edge of highly secret earthly technologies? … maybe. Could they be from our distant future via time travel? … no more likely than interstellar visitors.
What of our own ventures to the moon and maybe Mars? These are like exploring our backyard, but are no way close to inter galactic travel, so no comparison.
You should read a few more books.
Plutonium was unsuitable for gun type assembly due it it’s reactivity.
Never “tested” so never failed. Only thing tested was criticality that showed another method was needed to assemble a critical mass.
For some Freepers the World is flat. The Voyager probes. They have been moving through space nearly 50 years now at more than 10 miles a second. At that speed if they ran into something as big as a marble it would have destroyed the probe. They are almost one light day out. It is so big and empty out there I don't think most people realize , or are even capable of understanding, just how big things are .
I figure our Solar System has room for the expansion of Civilization for centuries before anyone is going to need an ID to travel. When it does get that crowded at some distance future, the stars themselves have plenty more room beyond that .
It’s tough to beat General Groves and “Now It Can Be Told”. Another good ‘un is “109 East Palace”.
Teller was actually bored with the conventional atomic physics at Los Alamos.
Even before the Trinity test accomplished, he was way out there and championing the “Super” bomb, or hydrogen weapon, to anyone who would listen. This caused a lot of problems, because he was getting everyone else off track during general discussions waxing eloquent about the possibilities of a fusion bomb.
Oppenheimer basically had to find something else for him to do, and keep him occupied, from being a distraction on everyone else.
It’s tough to beat General Groves and “Now It Can Be Told”. Another good ‘un is “109 East Palace”.
Teller was actually bored with the conventional atomic physics at Los Alamos.
Even before the Trinity test accomplished, he was way out there and championing the “Super” bomb, or hydrogen weapon, to anyone who would listen. This caused a lot of problems, because he was getting everyone else off track during general discussions waxing eloquent about the possibilities of a fusion bomb.
Oppenheimer basically had to find something else for him to do, and keep him occupied, from being a distraction on everyone else.
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