Recently in sci·ence Category

I’ve managed to get into a maybe one day argument again. It looks like a discussion with Matt, but really it’s a maybe one day argument. I suspect I’ll be having them for the rest of my life.

I wonder if it’s more about a different way of thinking, than a difference of opinion. I’ve never had a maybe one day discussion with anyone from a science background. That might have relevance.

See it’s really not about a difference of opinion at all. Because I don’t see there being any opinion involved. Which is also relvent, as those putting forward maybe one day points of view often claim that it’s all about differing opinions.

Let’s say it is.

I’ll quote Richard Dawkins

“When two opposite points of view are expressed with equal intensity, the truth does not necessarily lie exactly half way between. It is possible for one side simply to be wrong.”

The ‘argument’ is about the speed of light one day maybe being broken. Again (I get into this argument a lot)

Now let’s start off assuming either side could be wrong. That leaves us with two possibilities

1. The speed of light will never be broken
2. The speed of light will maybe one day be broken.

Now if this was a differance of opinion either side could equally be right. But it’s not. So one side is at the very least more wrong than the other

1. Lots of scientific proof and supporting evidence (including the fact the universe is working) that the speed of light is a constant
2. Nothing A few odd things we don’t understand that may or may not be related to the speed of light

So if we were to be generous and assign 1% to the speed of light being broken (i.e. not constant) then I’m still more likely to be right by near on two orders of magnitude. And that’s being really generous. The reality is that number (1) significantly outweighs number (2) by such a large order that number (2) is deemed false.

In fact the crux of the maybe one day is that whilst (1) appears to be correct, based on past experience we cannot dismiss (2) as ever being zero.

Which sounds true, but is also false, because if we could apply an “Reductio ad absurdum” argument and I can then say

Maybe one day we will prove that we will never be able to exceed the speed of light

Which holds true if we accept maybe one day arguments, which is then clearly false as it conducts the maybe one day argument, thereby showing that maybe one day arguments are not proof of anything.

And if you followed that all I’m really impressed.

The crux is, that “maybe one day” is a statement, not a truth.

It has nothing to do with being open minded, having a healthy scepticism and nothing to do with science.

“maybe one day we will exceed the speed of light” has no more meaning than “maybe one day we wont exceed the speed of light”.

Both can’t be true. Hence one must be.

I’m backing the one with all the science behind it.

When talking about weight and gym and stuff, I hear people often say "... you know that muscle is heavier than fat though, so you'll actually put on weight by going to the gym if you're doing a lot of weights ..."

Leaving for the moment that it's much harder to build a kilogram of muscle than it is to lose one of fat, so this never really happens this statement always bothers me.

See muscle isn't really heavier than fat. It's more dense. At least for me, if you say something is heavier, it's an absolute measure between two actual things.

So for example, a car is heavier than a bicycle. My mate Simon is heavier than me. 10 cubic meters of bubble wrap is heavier than my laptop. And 5 kilos of fat are heavier than one of muscle.

These are all absolutes. The one item is absolutely heavier than the other. And both items are explicitly mentioned. If you don't mention the items, but are just talking about generic things, I suppose you are implying the same volume of both, but for me this just rings as rather unscientific.

That's why when comparing two generic substances, like say fat and muscle, we should really talk about density. Muscle is more dense than fat, which then leads to muscle being heavier than the same quantity of fat.

In fact muscle is about 20% (give or take) more dense than fat. So the reason you'd be thinner with more lean muscle than fat is that it takes up less space, because it's more dense. Even though you might weight the same.

It all reminds me of the old school yard joke, "Which is heavier, a kilo of feathers of a kilo of lead".

In science, 'fact' can only mean 'confirmed to such a degree that it would be perverse to withhold provisional assent.' I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms - Stephen Jay Gould

I like that. A good way of saying Right, so you can't actually prove anything, absolutely, and maybe someday man will actually go faster than the speed of light, but in all honesty, man wont really, so lets go bark up a different tree.

Causality, at least in so far as it relates to going faster than the speed of light, means that the cause of an event has to happen before it's effect. You have a sore head (effect) because I hit you (cause) or you read the debate earlier on in the month.

Now if you break causality, you are pretty much allowing for time travel. If the effect can happen before it's cause, then you have to be able to shift around in time to do it. Either this means time travel is possible, or it means causality can't be broken. The effect (arrival) happens prior to the cause (departure) for other observers (i.e. not you). This creates a whole heap of paradoxes.

The classic one being the "kill your grandfather paradox." So you invent a time machine and go back in time. Kill your granddad (who falls under the category of "other observers") either be accident or design. The problem then occurs that if your grandfather was killed before he met your grandmother, then your dad/mom wouldn't have been born and neither would you have. So how would you have been able build the time machine that allows you to go back in time and kill yourself? Watch Back to the Future for further understanding, and to see the only practical use of a DeLorean.

On of the "Maybe One Day" arguments I have regularly had is the one that goes "Maybe one day we will be able to exceed the speed of light". This is a pet favourite hate of mine, as if you have studied physics, you know it's impossible. However if you watch a lot of sci-fi, it does seem like something where the problem is our primitive science.

It's not our science. The universe we live in would not be able to exist if you could exceed the speed of light. Or if the speed of light could change. Or even if it was different.

The problem with trying to explain something without using a lot of science, is that even a simple explanation can get quite complicated. So for this explanation below, I'm going to need you to accept two axioms.

1. The speed of light (itself) in a vacuum is a constant (It's exactly 299,792,458 m/s)
2. E = mc^2

Now both of these are provable. For the time being you need to accept that this is both true and provable. I'll try write another post to cover this, but trying to do this here would make this simple explanation of why we can't go faster than the speed of light not so simple, and I'm trying to keep things simple.

Now if you accept that energy and mass are proportional, by a constant factor, then the more energy you put into something the more massive it gets. In fact energy and mass are really two different forms of the of the same thing.

So if you want something to go faster, you need to put energy into it. And the heavier something is the more energy you need to accelerate it. So as you accelerate your object (for example your spaceship), it gets more massive, which in turn requires more energy to accelerate it faster, which in turn makes it more massive, which in turn requires even more energy to accelerate it, and so on and so on.

So to accelerate UP TO, you need an infinite amount of energy. You need more energy than exists in the universe. And even then your not actually exceeding the speed of light. This is why particles of light (photons) have zero rest mass.

So it's not that we don’t have a power or source or engine big enough to power our spaceship, it's that we don't have enough energy in existence and never will. It's simply not possible for a particle with mass let alone you and your spaceship to travel at or beyond the speed of light. It's not our level of science that prohibits it, but rather the fundamentals of the universe itself.