Hello, SFIA audio listeners.

In this month's Nebula exclusive, big alien theory,

we're asked at the reason alien civilizations might be rare

is because most aliens are huge.

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Many great minds have speculated about the possibility of life in higher or slash Isaac Arthur, and use my code, Isaac Arthur.

Many great minds have speculated about the possibility of life in higher or extra dimensions,

but only the late great Douglas Adams recognized the difficulty of going to war with them,

unless, of course, someone could walk out a way to file missiles at right angles to reality.

So welcome to another sci-fi Sunday here on SFIA, where we try to examine concepts

in science fiction and look at what the science has to say about them.

Today we're going to be discussing the concept of life in higher dimensions.

I'd imagine that for a lot of folks that conjures out of the idea of an

extra-physical dimension or two, or perhaps many, or alternatively, some higher or lower

planes of existence. I'll focus is on extra-physical dimensions, but we will be discussing both today,

and the reason why, as we'll explain, is that the two are almost inextricably linked.

Because what we really mean is a place where physics operates differently, and gravity, for

instance, works very differently if your universe has four physical dimensions and not three,

while concepts like entropy or energy conservation really shouldn't exist in your typical or heaven-like

...