I spent my life, my fortune, my family connections... I sold my children into slavery and my soul to Ilnarren... Wanted posters hang from from the Abyss of Shrondir to the expanse of d'o (most bearing passable liknesses)... I've sworn fealty to the Great Abitor and the Peasant of Myksyr... and betrayed them both... I've expended every facet of my being in this universe for this one moment...

My intrepid wizard desires a soul-satisfying revenge on his worst enemy! To that end, he has cast a stop-time spell. All the universe is frozen around him as he pulls back, spinning his arm in a disturbingly Popeyesque fashion, investing every fiber of his being to deliver a right-cross that would resound across the universe! But what happens to his nemesis (or himself) when that punch lands?

I'm trying to inject a bit o' science into my magical scenario and seek the greater wisdom of Worldbuilding.SE. Which of the two scenarios below is more believable? Your answers will be judged by how well you substantiate your claim. To that end, though this question appears very much to be about magic, your answers must be science-based with the exception that how the unverse came to a stop (aka, the setup of each scenario) is simply accepted as described in the scenarios.

Scenario #1

The name of the stop-time spell is misleading. What really happens is that I'm sped up to an infinite degree (or, at least to so great a degree that I cannot discern the passage of time for all others). I think, move, and react with instantaneous effect — and yet don't die in a moment due to me burning through all the energy my body pocesses. In short, though feeling just fine (thank you for asking!), I represent infinite potential while the rest of the universe represents none. Consequently, my fist moving at an unimaginable speed compared to the reference frame of my hapless (and soon to be dispatched) enemy and connecting with his head, results in a brilliant explosion of burning plasma that would make XKCD proud! It hurt! But it was well worth it.

Scenario #2

The stop-time spell was aptly named! Literally all the potential of the universe is brought to a stand-still, and like a river damed by the damned, the potential of the universe is absolutely infinite! I am unchanged, but also unable to discern the quantum quiver as the forces of time and space hold their proverbial breath, waiting for release! My fist drawn back... my anger explodes! And so does my hand as it impacts with what is quite literally the hardest thing the universe has ever seen! Or at least it feels that way, because what pitiful force my punch can bring is nothing against the restrained potential of the universe. Falling to my knees I cradle my hand and cry to the uncaring universe, "Noooooo!!!!"

Cry havoc! And release the unbound imagination of worldbuilding!

Which scenario is more believable?


  1. Pelinore points out that the atmosphere between my wizard's fist and his enemy's head is non-trivial. That's a honking good point, but for the purposes of this question, please ignore that. let's focus on the fist and the head.
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    $\begingroup$ Scenario #3 The comedy version: air friction from the (in relative terms) time frozen air causes his hand to instantaneously combust as he swings it, he watches in horror as his blazing hand burns to ash, stumbles back in shock igniting the rest of his body by the same process, burns up & turns to ash, the spell collapses & to his erstwhile enemy he appears to have simply turned to grey ash (no flames, burned out before the spell collapses) that falls to the floor & blows away in the breeze. $\endgroup$
    – Pelinore
    Dec 29, 2018 at 23:09
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    $\begingroup$ "lock the wizard in place" : I'd sort of imagine that one as like being encased in a very thin packing foam lattice, you could walk through it but it would begin to compact until you couldn't walk further, of course that leaves a vacuum behind you that you could reverse into, & then when the spell collapses you've a rush of air in to fill that vacuum : Of course perhaps you also have a problem then of trying to explain why you don't asphyxiate as new air to fill your lungs won't flow into the space vacated by your last breath, or why your lungs don't combust or get shredded as you breath? $\endgroup$
    – Pelinore
    Dec 29, 2018 at 23:26
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    $\begingroup$ ^ It all depends on the parameters of your spell, what it's internal logic & rules are, how it works. $\endgroup$
    – Pelinore
    Dec 29, 2018 at 23:30
  • 1
    $\begingroup$ One assumption might be anything touching skin (including air) is brought into the same time speed, you want to avoid the possibility of bits of clothing falling outside his personal time-bubble (sort of like a loose bit of cloth snagging on a nail) you maybe extend it to a millimeter or two from his skin, a possibility then might be touching a person brings them entirely into your time-field rather than just the bit touched? $\endgroup$
    – Pelinore
    Dec 30, 2018 at 0:03
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    $\begingroup$ For all actions in the universe, under the normal pace of time, speed is calculated by dividing the distance covered by the time taken. With time suspended, calculating the speed of your fist causes a divide by zero error which crashes the entire simulation which your wizard thought was reality. $\endgroup$ Dec 30, 2018 at 2:23

2 Answers 2


Scenario 1 is the winner (sort of)

The thing about your question that needs to be addressed is something a man named Albert once said; "Everything's relative".

In that sense, scenario 1 is the simplest and easiest to explain. By speeding up yourself, you increase the velocity and potential energy of your fist by comparison to the target. You'll probably still destroy your fist in the process, but it's easier to explain the kinetic energy difference by adding energy than by removing it. For that reason, scenario 1 wins by virtue of Occam's razor insofar as it's the simplest solution.

The problem with scenario 2 as I see it is that it's very difficult to reduce the kinetic energy of something static, that is to say with a kinetic energy value of close to 0. This is essentially the same as the refrigeration problem all over again. Just how do you use energy to make something colder, when making something colder means reducing its internal energy value?

In the modern world, we do that by heat exchange. We heat something up, but in such a way that the only way it can draw that energy is from an enclosed space we want to cool down. By doing so, we extract the energy from that enclosed space, and refrigerate it.

In order to do that in your scenario 2 above however, we would actually need negative energy. Why? Because a static head still has mass, which means that it still needs the same amount of energy to act on it as force to do damage to it. So, slowing down time around it ONLY helps if that somehow decreases the amount of force that will damage it, and the only way I can see that happening is negative energy.

So - scenario 1 solves the problem by increasing energy to the blow. Scenario 2 can only solve the problem by introducing an energy-exchange model that either reduces the mass of the static object, or can reduce its kinetic energy value to less than zero. Ergo, scenario 1 is simpler, and wins (thanks to a Franciscan monk from the 13th century).


Scenario 1 but hit him very, very slowly (in your time-frame) and wear an internally padded iron glove. Otherwise you will destroy your fist and most of your arm and he will be instantly killed by the shock-wave through his brain. The iron will do the damage through its own momentum and won't be stopped like your hand would be. If you want him to suffer then he has to be incapacitated not killed outright. A sword would be better though perhaps not so satisfying as it would chop off his jaw without killing him (can't believe I'm writing this). If you want yourself not to suffer then take it easy. Preferably practise on nearby inanimate soft objects first to judge the effect. Start with the cushions from his sofa and hit them very lightly - see what happens.


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