A federation of alien spacefaring nations is doing basically the opposite of prime directive: they are jamming the Solar System, preventing us from leaving it.

They are doing so by placing some devices right outside the Solar System, and these are the cause of special relativity and the speed of light problem.

Without jamming, in normal conditions, light speed is instantaneous, and there's no limit to the speed you can achieve.

How pseudo-plausible is that? I can use handwaving of course, but I'd rather use as few as possible.

What other effects might this have? Like nuclear weapons no longer working? (I don't think so, but I'm not sure.)

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    $\begingroup$ Nothing works in a world where the speed of light is infinite. The speed of light is intimately linked to the strength of electric and magnetic forces, $c = 1 / \sqrt {\varepsilon_0 \mu_0}$. If the speed of light is infinite, this means that $\varepsilon_0 \mu_0$ vanishes. Chemistry (including basic life processes), eletric generators and electric motors, etc. stop working. $\endgroup$
    – AlexP
    Commented May 27, 2020 at 7:45
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    $\begingroup$ so shouldn't we be thankful otherwise we will be hit by every single energy output from every damn star right now :D $\endgroup$
    – user6760
    Commented May 27, 2020 at 9:49
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    $\begingroup$ Light would still need to move at the speed of light, but that's not to say aliens couldn't be somehow jamming whatever allows FTL in your universe (hyperspace transit, the formation of pocket universes, etc.) so that the physics we can experiment on but not observe outside or solar system is altered. $\endgroup$
    – DWKraus
    Commented May 27, 2020 at 13:30
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    $\begingroup$ You would have to explain why we observe red shifts (and corresponding aging of galaxies &c), black holes, gravitational waves... $\endgroup$
    – jamesqf
    Commented May 27, 2020 at 16:33
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    $\begingroup$ That idea has been used in a short story, "Local Effect" by D. L. Hughes, in Analog, April 1968. The aliens in the story "jammed" us unintentionally, as a side effect of a derellict space drive. See this Q&A from scifi.SE: scifi.stackexchange.com/questions/155780/… $\endgroup$
    – user14111
    Commented May 28, 2020 at 3:18

8 Answers 8


The Copernican principle

As L.Dutch pointed out, this would violate the Copernican principle, which essentially states that there's nothing special about observing the universe from any one place. Granted, this is not easy to test, as we humans only sit in one tiny portion of the cosmos. However, it's possible that the Copernican principle is incorrect, and tests have been devised and, in some cases, carried out:

  • Observing distant supernovae can tell us whether we live in a large underdensity (Clifton et al. 2008)
  • That same underdensity would influence our observations of the cosmic neutrino background (Jia & Zhang 2008)
  • Unexpected changes in the Hubble constant at different redshifts would indicate that we on Earth are privileged observers (Uzan et al. 2008)
  • Future radio telescopes could test our assumptions of cosmological homogeneity and isotropy (Schwarz et al. 2015)

. . . and so on and so forth. Most of these are not related to the problem at hand, but any positive result would indicate that the Copernican principle may be wrong. It's still quite possible that this is the case. I don't think many astronomers subscribe to that view, but it's not yet out of the question.


I'm going to stick to the cosmological effects of this sort of change, and what we'd see on Earth. The immediate consequence is that the night sky would, for a short while, turn mostly black.

Consider two photons from a distant star, traveling towards Earth. One is emitted just before the jamming begins, and therefore reaches Earth instantaneously. The other is emitted just after the jamming begins; it travels instantaneously to the edge of the Solar System, but then takes a time $\tau=r/c$ to reach Earth, where $r$ is the radius of the jamming region. The Solar System is large (the Oort Cloud is arguably a light-year or two in radius), so it would take about a year or two for the second photon - or any other photons emitted just after the jamming began - to reach Earth. But in that intervening time, there would be no stars in the night sky on Earth.

We would also notice that light from all sources outside the Solar System would arrive at the same time. That is, light from a source 10 parsecs away would arrive at the same time as light from a source 100 parsecs away. This is because it only takes them a time $\tau=r/c$ to reach Earth; outside the Solar System, the light travels infinitely fast. We'd have many of the astronomical consequences we would get in a universe where there's no speed limit:

  • No redshift of sources beyond the Solar System, as $z=0$ when $c\to\infty$.

  • As a consequence of the above Olber's paradox would no longer hold: the sky would be bright, as it would hold light from all of the objects in the (presumably infinite) universe.

  • We would see distant galaxies as they are, not as they used to be.

  • Gravitational waves would travel instantaneously fast, as they travel at the same speed as light - which is now, outside the Solar System, infinity.

  • Spectroscopy is either out the window or severely modified. I'm not sure if you could build a self-consistent model of electromagnetism, let alone electronic or molecular transitions, so spectral lines are likely right out.

  • Even in the event that lines are produced, most broadening mechanisms (e.g. pressure broadening, thermal broadening) and line diagnostics wouldn't exist because of the aforementioned lack of redshift and therefore the Doppler effect.

What this means for science, from an observational perspective:

  • We can no longer use distant supernovae to measure the expansion of space.

  • We can't use the radial velocity method to detect exoplanets.

  • Determining galactic rotation curves would be exceedingly difficult, if not impossible.

  • Early-universe cosmology is suddenly almost impossible, as we can't see protogalaxies in the earliest stages of formation.

  • Without spectroscopy as we know it, determining the composition of celestial objects is extraordinarily difficult, if not impossible.

All of this is just the tip of the tip of the tip of the iceberg. In other words, you can throw the majority of astronomy and cosmology right out the window - that is, if the infinite speed of light doesn't make things like stars and fusion impossible, and there's still an outside universe to observe.

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    $\begingroup$ Lasers would also be impossible, and astrophysical masers wouldn't happen (en.wikipedia.org/wiki/Astrophysical_maser). Spectral lines, if they were produced at all, wouldn't be subject to Doppler effects...not just overall redshift, you also wouldn't get line splitting from rotating sources or line broadening from the motion of individual atoms. They'd basically have to simulate a universe with physical laws matching our local region and somehow present us with a view that matches that simulated universe across the EM spectrum and in neutrino and gravitational radiation. $\endgroup$ Commented May 27, 2020 at 20:03
  • $\begingroup$ @ChristopherJamesHuff All excellent points. $\endgroup$
    – HDE 226868
    Commented May 27, 2020 at 21:16

The basic assumption behind our constant effort in producing physics theories is that they are valid in every place of the universe.

This assumption has never been disproved so far, and if it was as you say, we would observe some hint of this jamming.

For example we would observe a discrepancy between the distance of galaxies estimated via the Cepheid method (which uses only the magnitude of some stars) and the same distance estimated via the red shift (which is due to the spacetime dilating while the light travels at c through it).

It would also be difficult to keep order in the light reaching Earth: the deeper we look in space, the further back in time we are looking in time, so we observe different stage of the universe life. The jamming should take that into account. Even if handwaving might be used to explain this, a space probe observing the deep universe away from Earth but still in the solar system would observe something different.

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    $\begingroup$ is that they are valid in every place of the universe. Which may not be true - one of the many problems still unresolved in physics $\endgroup$ Commented May 27, 2020 at 6:16
  • $\begingroup$ Hmm... Sounds somewhat familiar... $\endgroup$ Commented May 27, 2020 at 14:33
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    $\begingroup$ @chepner false. We've been observing signal delay across the universe. The cosmic microwave background is the furthest light we can see. Doppler shift is how we found out the universe is expanding. There's no Doppler shift if the speed of light is infinite. And you know what else changes when you change the speed of light? Its index of refraction. In other words, as soon as light reaches our solar system, it would turrrrrn. Unless you are right in the middle of the sphere, you would see but a tiny speckle in the midnight sky, an entire hemisphere's worth of light compressed into a single point $\endgroup$ Commented May 27, 2020 at 15:46
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    $\begingroup$ Any evidence we observe on Earth necessarily passes through the purported jamming field. You can't claim anything about how things work beyond the field. $\endgroup$
    – chepner
    Commented May 27, 2020 at 15:49
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    $\begingroup$ @chepner Well, it must yield consistent observations across two completely different regimes of physical law. Hard to to. It's easier to just assume the bubble is a holographic field projecting an image, hiding something that looks completely different than what we actually see and let it be at that. $\endgroup$ Commented May 27, 2020 at 16:06


Refraction is based on light moving at different speeds through different materials. As soon as light travels everywhere instantaneously, all of optics goes out the window. Lenses, prisms, filters, lasers - it all doesn't work or is radically different. Which means that the aliens outside our system are operating under a completely different set of physical laws. Light may travel instantaneously, but the aliens may not be able to see it because it cannot be focused by eyes or instruments.

The idea that special relativity was fundamentally wrong was used as a throwaway comment in explaining the aliens' interstellar travel in The Legend That Was Earth, but the author was smart enough not to explore the massive impacts on physical laws inherent in this idea.


And God saw the light, that it was good: and God divided the light from the darkness

Our keepers have produced a habitat for us where physics works in a way that keeps things running and keeps us alive. Things we perceive as coming from outside our bubble must be simulations of some sort, like the distant ocean background pasted up against the back wall of an aquarium. The fish cannot explore that distant ocean background.

  • $\begingroup$ I would go without the "everything we see outside is just plainly fake", if possible. Not a strict requirement, so the answer is still valid, but a mild one if I may. $\endgroup$
    – o0'.
    Commented May 27, 2020 at 16:55
  • $\begingroup$ Distorted, yes, sure. Just not completely fake. $\endgroup$
    – o0'.
    Commented May 27, 2020 at 16:56

Not plausible at all, unless everything we see out there is faked.

The aliens would have built a "bubble" all around the Solar System (or a good part thereof - there is something like that in Giant's Star by James P. Hogan, and in The Crystal Spheres as well), and the inner wall of the bubble is a sophisticated "screen". Appropriate emitters simulate a relativistic universe.

This solarpsistic Truman Show includes, for example, the fact that some stars such as T Pyxidis or T Tauri variable stars emit a distinct time-dependant light signal (such as a nova explosion or a luminosity variation), and then we may see the light from this event reflected back towards the Earth with a measurable delay of weeks or months, as the "flash" illuminates e.g. a large nebula, the nearest parts first.

Were c infinite, the nova flash would illuminate the whole nebula at once.

Also, other phenomena relying on relativistic physics and gravity traveling at the speed of light (e.g. a star orbiting a black hole) would evolve differently were c different and practically infinite.

This endeavour would need to have been initiated some eight or nine billion years ago, since the Sun's very existence, let alone our biochemistry, relies on the speed of light being more or less its known value.

The barrier might have to take into account mass and thermal exchange (haven't done the math). Over billion of years, with a star and its solar wind locked inside, effects on orbits and ecosystems might be significant.


Without jamming, in normal conditions, light speed is instantaneous

The universe outside of the illusion would be unrecognizable to us. Time and space in it would not exist as we know them, if they even existed.

Tachyons are hypothetical particles that travel faster than light. A few excerpts from the wiki:

As noted by Albert Einstein, Tolman, and others, special relativity implies that faster-than-light particles, if they existed, could be used to communicate backwards in time.


(...) in the case of a hypothetical signal moving faster than light, there would always be some frames in which the signal was received before it was sent so that the signal could be said to have moved backward in time. Because one of the two fundamental postulates of special relativity says that the laws of physics should work the same way in every inertial frame, if it is possible for signals to move backward in time in any one frame, it must be possible in all frames. This means that if observer A sends a signal to observer B which moves faster than light in A's frame but backwards in time in B's frame, and then B sends a reply which moves faster than light in B's frame but backwards in time in A's frame, it could work out that A receives the reply before sending the original signal, challenging causality in every frame and opening the door to severe logical paradoxes.

It's like people from all times and eras being able to communicate with each other. This, with the causality violations, means time makes no sense outside the bubble.

If you handwave that, there is still the problem of light being very fast. We've had another question, which was specifically about that: What would happen if the speed of light was fundamentally faster?

Remember the formula $E = mc^2$? If you increase the value for $c$, it means converting mass to energy gives you more energy per unit of mass. This means all nuclear reactions are way more energetic. If $c$ is infinite, then a single particle undergoing such conversion can cause the universe to collapse on itself, maybe generating another universe in the process. In the words of the immortal Douglas Adams:

There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.

There is another theory which states that this has already happened.

  • $\begingroup$ I believe this paradox doesn't apply here, I've stated my question specifically to avoid this and similar ones. Nothing is traveling over the speed of light in this case. It's the speed of light that it is higher (or infinite). $\endgroup$
    – o0'.
    Commented May 27, 2020 at 16:58
  • $\begingroup$ (the rest of the answer is quite good, though) $\endgroup$
    – o0'.
    Commented May 27, 2020 at 16:59
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    $\begingroup$ Downvoted because you're assuming the correctness of relativity in a universe where relativity is stated to not exist. $\endgroup$
    – Mark
    Commented May 28, 2020 at 0:38

Let me try and answer this question from a very theoretical point of view. But first, we need to set up some assumptions. The principle of relativity is a good assumption to start with.

Now, as the OP mentions, the aliens have set up devices just outside the solar system to jam us and prevent us from leaving. Fair enough. But can we sit inside our solar system and observe this? Probably not, because the aliens would not like us to find this out. So they might set up a system where these devices they have placed is basically a sphere around us (we are inside a Matrioshka brain?) , and they simulate the outer universe. Possible? Maldacena would like to agree with you. There is a theory that intuitively states that the description of a volume of space can be encoded on it's surface. Given the ability for instantaneous communication of the device outside our solar system, it can have a number of parallel processing components anywhere in the universe if required to fine tune a simulation for the tests that humans do. This means that no observations that we do without going outside the solar system (if possible) would not reveal the actual structure of the universe.

But what about local observations (observations withing the solar system)? No changes from our known results. Standard relativity applies, so all's well.

Fine, so the aliens can hide themselves till we venture outside. But all of this was deduced assuming that the aliens exist and can jam a bounded region. Let's talk about the second assumption fast. Looking at the structure of the universe right now, it's like this


where I would like to stress that this is a projection of the universe onto a 2-D plane, and that the outer universe might not be flat as shown, but may have a different structure.. The space inside the circle (region $R_1$ is our solar system), and the rest is obvious from this observation. Now, if there are any inconsistencies in a universe with a closed and bounded region having a different light speed than the rest of the universe, then it's bound to occur at the intersection as it is the point of discontinuity. To that end, how can two points, say $A$ and $B$ on the boundary communicate? Since the region bounded is convex (had it been concave, there would still be points that will lie in a locally convex region), the straight-line-communication would have to go through our universe, but then they would be limited by the speed of light of our region and also have a chance of giving themselves away. To avoid such things, they can use a external point $C$ and since $A\to C$ and $C\to B$ is instantaneous, $A\to B$ is also instantaneous.

This solves the problem as to what would be the speed of light on the boundary (if it makes sense, like using continuous refraction to keep it on the circle or something like that). How? Define a relation $\sim$ on the set of points $R=R_1\cup R_2\cup R_3$ (where $R$ is the whole universe) such that for $x,y\in R$, $x\sim y \iff x$ and $y$ can communicate instantaneously. Observe that the relation is trivially reflexive and symmetric ($x\sim x$ and $x\sim y\Rightarrow y\sim x$) and by the argument in the above paragraph, $x\sim y,\ y\sim z\Rightarrow x\sim z$ and thus the relation is transitive. This shows that this an equivalence relation and hence $R$ is partitioned into 2 subsets $X,Y$, the former where all points can instantaneously communicate, the latter cannot. Since $A,B\in R_3$ can communicate instantaneously and since $A,B$ was arbitrary, $R_3\subset X$ and thus $X=R\setminus R_1,\ Y=R_1$.Thus light speed is infinite (in a mathematical sense) on the boundary.

So far, no inconsistencies.

Now we ask the following question. How will two particles, one in $R_1$, the other in $R_3$ communicate?

We first look what happens if they are electrically charged. This won't be a problem because of electromagnetic shielding. The aliens can hide any traces of them, electrically. But what happens if one looks at gravitational effects? Can these devices hide geometrical distortions in spacetime? Hard to say. If there is a particle in $R_3$ that bends spacetime in a way that we can detect using the particle in $R_1$, then the detectors might take in account the effects and simulate a visual program for us to see to validate our observations but giving no information about the outside universe. Possible I suppose, but very very difficult. Might be closer to impossible, but here I run out of maths in this regard.

So let's take it that they can keep us in the dark even though we try to measure outside stuff via things that are globally affected.

Then, is there any known theory that stops them from doing so> The Copernican Principle? Not so much a problem, because it's a local issue and happens in a closed and bounded region (I can say compact, but let's go with this). Because suppose you throw out $R_1$(mathematically). Does $R_3$ have a problem with that? No, because all points in $R_3$ can communicate instantaneously and hence communication-geodesics (the line of fastest communication) can circle round the hollow region without any problem. There might be some physical issues, but none fatal enough. This does break homogeneity though. But one can characterize the hole as a singular region, akin to a black hole and shut physically it out by not communicating with it. There will be residual information leakage and other effects, but nothing inconsistent that would cause a logical collapse.

One might observe that no information about $X$ ever reaches $Y$ and hence $R_3$ is a horizon, and hence there should be a radiation quite similar to Hawking or Unruh radiation (random particle emission), and we can observe this to know that something is wrong, and there exists a horizon. This line of argument does not work, because we can't observe this, as we would be living inside, roughly speaking, an inverted black hole. The leak would be outside, into $R_2$.

Think as I may, I cannot see any reason why the aliens cannot jam a bound region and not give themselves away. This leads us back to the assumption that the aliens exist.

The existence of the aliens is an extension to the question of whether a self-consistent universe with an infinite light speed exist. Possibly... yes. Well, at least, the following provide evidence for such a universe to be consistent.

Assuming the principle of relativity, and that the universe is isotropic and homogeneous, Sir Palash B Pal tells us that two kinds of relativistic systems are consistent. One with a constant $K=0$ and the other with a constant $0<K<\infty$. He argues that the first case arises from the assumption that time is absolute, which is basically a universe where Galilean invariance works ($X$)and the other is basically our universe $Y$. Until we go poking around $R_3$ (when we will obviously detect the presence of a sphere), $R_1\cap R_2=\phi$, and $R_1$ is closed and bounded and hence is consistence.

How shall the dynamics of such an universe work? Pretty much just classical mechanics, non-relativistic QM, and the like. Electromagnetism is inherently relativistic, but non-relativistic electromagnetism, the so called Galilean electromagnetism, exists and is consistent with instantaneous light speed. Interestingly, spin-orbit coupling goes out the window in such a universe. A rather boring set of atomic orbitals. What about gravity? Gravity in $Y$ has a geometric structure, which can be explained by General relativity. But in $X$? Fortunately, there is a consistent geometric formulation of geometric Newtonian gravity, called Newton-Cartan theory. Again, the geometry in $X$ and $Y$ has to agree (and be differentiable) at $R_3$, which the devices probably will have to do if they want to avoid detection. Is it mathematically possible? Yes. The reasons are involved, but it works.

Can such a universe have a beginning? Hard to answer, possibly yes? But the birth of stars and everything would have to be modified. The existence of mass-energy equivalence is purely relativistic, but strictly speaking, such a thing cannot be said to be inconsistent with classical physics. One can insert such a term and get away with it because all it would do would be to shift the energy scales from 0 to some other value. But would it have any physical meaning? No. An example to why this is so is simple. Take a particle of some mass. Let it radiate two photons, one to the left and the other to the right, both of equal wavelength. Let's see what $X$ and $Y$ can deduce. First in $Y$. The center of mass frame of reference says that the particle stays at rest because both the photons carry equal momentum. But in a moving frame, one of the photons would have higher energy, and hence higher momentum and thus the body would have lost some momentum. To reconcile both the observations, they deduce that the body has lost some mass. But in $X$, wavelength does not make sense. All radiation are instantaneously propagated and hence the word loses its meaning. Both the photons have the same energy (it it makes sense) and hence same momentum in whatever frame they are observed and hence makes no deduction about the particle's mass or energy. In other words, stars possibly cannot exist.

First line of thought that can produce an inconsistency found! If no stars are formed, then no higher elements as there would be no nucleosynthesis, and hence no life. I do not believe life can be formed with just the lower few elements, and pure consciousness is not something that can be defined with current theories that we have. Is this enough to kill off the aliens? Highly probable, but there can be one way (more than one way) the aliens can still crop up in such a bleak desolate universe.

A stabilized rotating Kerr black hole! Or something similar.

Let's suppose the aliens are a Type-III or Type-IV civilization (likely the latter) residing in a universe similar to ours. Maybe something similar to the extraterrestrials in Arthur C. Clark's 2001: A Space Odyssey. They have discovered a theory of how to jam regions of spacetime in a Galilean universe to induce a Einsteinian universe in such a place. They also have the technological know-how, only no way to test. They also have the potential to open a portal and pass on their information to other universes in the multiverse. One such thing reaches a universe that looks like $X$, a Galilean universe. They see no life, just bleak primitive elements and compounds spread across a desolate, barren and dark landscape. The aliens reconstruct themselves in this universe, and then start constructing their device, on a large scale, which, according to them, would encompass several thousands of galaxies in their universe. Once done, some of them stay inside the structure, and the rest leave the universe for other work.They generally don't disturb the device, except to look at what the situation is on different places inside the region. Due to relativity now doing it's work, stars form, heavier elements arise and a miniature Einsteinian universe starts. Ages pass, and life births on several planets, one of them being Earth in the Solar System (their names are different to the aliens, but we call them so for easy identification). After several million years, intelligent life starts on Earth, none of the others being fruitful. The aliens are happy with their simulation, and they construct a similar device just around the solar system. After completion, they deconstruct the outer device.

This obviously puts us in the situation the OP has right now, albeit not the process the OP was probably thinking.

I don't have anything to add right now, but if I do find anything else, I would add them up.


Not really

One of the key observations Einstein made when developing Special Relativity is that electromagnetism and Newtonian mechanics are invariant under the action of different transformations. Individually, each theory lets you run through your lab at whatever (constant) speed you like and still produces results that are consistent with those you'd get if you'd stood still, but, because the results transform differently between the two theories, when put together they produce contradictions

Einstein solved this by making the smallest corrections to Newtonian mechanics necessary to bring it into alignment with electromagnetism (essentially replacing the Galilean transform of Newtonian mechanics with the Lorentz transform of special relativity)

We don't want special relativity to be true so, what if we instead try to adjust electromagnetism in the smallest way to make it compatible with Newtonian mechanics? Well this is kind-of what the luminiferous æther was trying to do and, unfortunately, Poincaré and Lorentz eventually showed that, in order to make it compatible with our inability to measure our movement through the æther you end up getting identical predictions to special relativity (just with some additional theoretical overhead and in a form that extends less easily to include gravity)

For special relativity to be the result of outside influences, either Newtonian mechanics or electromagnetism needs to be entirely faked

That means your aliens need to be able to control every interaction between every particle in the zone they're jamming. This isn't just micromanagement, or even nanomanagement, this'd be more like femtomanagement (electrons living at the femtometre scale) and would require your aliens to be essentially omnipotent and incredibly dedicated

Alternatively, you could go for the simulation hypothesis and have us just be a program running inside a non-relativistic universe but that's arguably a more drastic separation from the external universe than a bunch of obssessive gods messing with us for kicks


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