Tag Archives: science

Ridley Scott Lied to Me (Ask a Guy in an Unrelated Field)

Every now and then science comes up in the news. Since none of us at The Cool Ship are scientists, we turn to the one science-y person we know – Colleen’s husband, Mike Padgen. Mike is proud to be The Cool Ship’s resident non-expert and our Guy in an Unrelated Field.

So you finally got around to watching Prometheus when your wife was out of town. What did you think of it?

It was fine. I enjoyed a lot of it. It was well made, but the whole time I kept thinking, “When is this guy going to show up?”

Georgio from tumblr

Really, Ridley Scott? Image courtesy of Tumblr.

The Ancient Aliens guy?

Yeah. It’s just such a silly show – “Why would these people have done this? How could this happen? Must’ve been aliens!” To make a serious movie using those ideas, it’s just boring to me. The possible answers to how life can come from non-life and, for that matter, what distinguishes life from non-life, are so much more fascinating than anything conclusions we could possibly draw by saying, “Must’ve been aliens!”

So then, if Ridley Scott is lying to us and it wasn’t aliens, how did life on Earth come about?

Well, it’s important to preface the rest of what I’m going to say with the fact that we will never know exactly how it happened on Earth. What we can know (even if they’re not fully understood as of yet) are plausible mechanisms by which the conditions on Earth 3.8 billion years ago (or so) would yield simple, self replicating life forms.

Life on Earth started 3.8 billion years ago?

Well, there’s no exact date, but it seems to have started soon after the Earth cooled enough to have liquid water on it, which happened when the Earth was only a few hundred million years old. Interestingly, the fact that life came about fairly quickly on Earth lends credence to the idea that life is common throughout the universe, even though we have no direct evidence of that.

So how could non-life become life?

The primordial soup, approximated in the famous Miller-Urey experiment, is not exactly right. One missing piece in that hypothesis is the lack of thermodynamic push – there is nothing pushing the ingredients in the soup to sustainably react with each other. Instead, it is thought that life originated in hydrothermal vents at the bottom of the sea, which provide both reactive hydrogen and a state of thermal disequilibrium that can drive the formation of complex molecules. The porous rocks in these vents contain small compartments that allow the organic molecules to accumulate, allowing further reactions to occur.

Since all life on this planet uses DNA to store genetic information, it is thought that the last universal common ancestor must have also had DNA. However, the very first self replicators could not have used DNA due to a chicken-and-egg type problem. The proteins that duplicate DNA are also encoded by that DNA. There is no selective pressure that would ensure that the genes responsible for duplication are maintained. It has therefore been posited that the initial life forms on this planet used RNA, which is able to catalyze its own duplication.

But where did the RNA come from?

where did the lighter fluid come from

Come to think of it, where did the lighter fluid come from too?

Several organic molecules, including precursors of amino acids and sugar, can be formed in space and have been found on asteroids and meteors. The period before life arose, the Earth was bombarded with asteroids, so these interstellar organic molecules were delivered from space.

So it was aliens!

No, that’s not what I’m saying at all. These organic molecules form spontaneously in space, and with the right conditions on earth, can be organized into nucleic acids and proteins and all the other stuff life needs to exist. There is no infinite regression required.

Sounds like it was aliens.

Ugh.

Georgio from tumblr

Called it.

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Ask a Guy in an Unrelated Field: The Science of Immortality

You have questions, and he has… sort of answers and maybes. That’s right, it’s time for another “Ask a Guy in an Unrelated Field.”

By: Mike Padgen

In your last article, the level of handwaviness  was so astounding.

You’re welcome.

Uh, thanks? Well, as I was saying, it was so astounding, I just can’t help coming back for more. So, let’s get to it. How do I live forever?

Wait, what? That’s your question for me?

582px-White-Rabbit-making-elixir-of-immortality

This apparently has something to do with immortality. Thanks Wikicommons!


Yeah, isn’t technology gonna let us live forever? The singularity is near, and all that?

I’ll get to the singularity in a second, but let’s start with what technology can do for us. Advances in medical science have certainly improved our quality of life and our ability to fight diseases that were once death sentences, and will continue to do so. But extending our lifetimes past the current limit (around 125 years) is far away, unless, of course, you can pull off the Three Stooges Syndrome.

Keep in mind, medical progress is slow. For example, when the Human Genome Project started, it was thought that, once we could sequence someone’s genome quickly and cheaply, we would be able to provide personalized medicine that would, among other things, allow doctors to correct mutations a person inherited from their parents through gene therapy, either preventing or treating a whole range of diseases – essentially revolutionizing every aspect of health care.

[Ed. note: That was an impressive run-on sentence. I’m going to let it slide since I’m not 100 percent sure where to cut it off.]

Mad scientist

He looks legit. I’d trust this fellow with my mortality. Image courtesy of dzingeek on Flikr.

Hey, Ed., get out of here!

Where was I? Basically, personalized medicine was supposed to be available by now. Unfortunately, we are not as simple as the pea pods everybody learns about in high school biology. Craig Venter (also of “synthetic” life fame), whose entire 6 billion nucleotide genome has been published, noted that even his eye color could not be determined from examining his genome. It turns out that knowing the nitty gritty details of things like the epigenome and the microbiome, among other “-omes,” of a person may be required to deliver truly personalized medicine.

Ok. But I want it now.

Well, even if we figure out ways to treat every form of cancer, infectious diseases, and all the other scary ways Mother Nature tries to kill us, our bodies will still age and deteriorate. There are a lot of people trying to understand how and why we age, and from that what can be done to slow the process of aging.
Stem cell therapies might be able to replenish our old tissues, but that becomes a problem with the brain. If your brain cells are replaced, you lose the connections that have been established over your lifetime – you would lose your memories and you wouldn’t necessarily be you.

So this is where technology comes in and saves the day and we all become uploaded… 

I’m gonna stop you right there. Ray Kurzweil and Co. do believe that once a sophisticated enough model of our brains can be created, we will be able to transfer our consciousness onto a computer. And yes, as computer technology advances past the end of Moore’s Law to Post Moore and beyond, we will eventually have computing power that matches our brains.

But our understanding of how our brains work is still in its infancy (Thanks a lot, “Ethics Boards”). Essentially, the hardware isn’t far off, but the software will be.

But let’s say at some point in the future someone copies their consciousness perfectly onto a computer that is somehow attached to a body that provides the same inputs as that person’s actual body. The non-deterministic behavior of the quantum world will cause the person’s brain and the copy to diverge almost instantaneously, meaning the copy will no longer be an exact copy.

Hmm… when do I get my adamantium skeleton then?

I think we’re done here.

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