Sunday, February 23, 2025

A Universe Made for Life

Mandelbrot fractal

Consider that the universe right after the Big Bang1 was a small, cold, rapidly expanding cloud of mostly hydrogen nuclei—that is, protons—and loose energy like gamma rays, x-rays, and microwaves. Just a mist of mostly non-reactive stuff: protons eventually gathering electrons to themselves and clinging to each other, holding hands and heading away into the darkness.

That is a universe in which life could not exist. Two molecules of diatomic hydrogen rubbing together would create no more than transitory friction. And then they would bounce away. It wasn’t until the outward flight slowed down a bit and gravity could take over that things started to happen.

When things began cooling down and those hydrogen atoms could approach each other, gravity drew them together. And when enough hydrogen atoms got close enough, jostling against each other, the inward pressure ignited a fusion reaction. Then hydrogen atoms became helium atoms, and the energy that was released heated the mix, so that outward pressure from excited gases balanced the attraction gravity. And then there was light and heat in the universe.

The fusion reactions created successive combinations of protons and eventually included neutrons. When the hydrogen at the center of a star begins to run low, helium nuclei fuse to become carbon. Then carbon fuses to oxygen and neon, and oxygen fuses to become silicon and sulfur. The process continues until iron atoms begin to form. These nuclei are too heavy for normal stars to fuse, the fire starts to die down, and the star eventually first collapses and then explodes. Pressures inside that explosion fuse the heavier atoms and scatter everything to great distances—out to where dust and gas can begin forming new stars with richer content.

Generations of repeated fusion and collapse provided the atoms and molecules that are the basic building blocks of life. Dust and gas also formed the planets around those later stars, providing the environments in which life could form. And the stars themselves provided the energy in the form of heat and light for various atoms with their complex electron bonding to join into molecules that could react with each other.

This process takes place in not just our solar system or our own Milky Way galaxy, but inside the 100 billion to two trillion galaxies that spread across the visible universe. Everywhere we look, we can see points of light representing stars. And we know of almost 6,000 extraterrestrial planets in our local neighborhood alone. Many of them are close enough to their star to have liquid water—the molecule comprising hydrogen and oxygen—in their makeup without being so close that their surfaces are scorched earth nor so large that they are simply balls of dense gas without an underlying surface. Water and someplace to put it are the basis of life—at least the kind of life we know and understand.

So, the building blocks, the environment, and the driving energy of life is all around us, out as far as the eye can see. And that means life itself must be all around us.

1. Well, if you can accept the Big Bang, a microparticle containing all the matter in the now-visible universe, compressed to an intense point, denser than a black hole’s heart, as the starting point of all that we now can detect. We only believe in this incredible situation because we noticed the universe was expanding in all directions. Then we calculated a rollback and decided it started somewhere as a point of nothing about 13 billion years ago. And everything since then has been theory and mathematics. In my opinion, the Big Bang is another creation myth, like God dividing the firmament, and no one really knows.

Sunday, February 9, 2025

Excitation and Regulation

Robot head

What does the human brain have that the current crop of artificially intelligent platforms doesn’t? In a word: hormones. Everything we think, say, and do is moderated and modulated by a background system of excitation and release of chemicals that provide a response in either pleasure or pain, faith or doubt, up or down.

Here are some of the main chemicals:

Serotonin, or 5-hydroxytryptamine (5-HT), is a monoamine transmitter that also acts as a hormone. It carries messages between neurons in the brain and throughout the body’s peripheral nervous system, especially in the cells lining the intestinal tract. It influences learning, memory, and happiness, as well as regulating body temperature, sleep, sexual behavior, hunger, and in some cases nausea. It regulates mood and mental focus, and its lack can lead to depression and anxiety. (Cleveland Clinic)

Dopamine (C8H11NO2) is a neurotransmitter that is also released in the brain and travels through the body. Certain neural circuits or pathways in the brain trigger the release of dopamine, which gives the sensation of pleasure and functions as a reward system. Like serotonin, it affects mood, memory, attention, learning, and motivation, as well as sleep, kidney function, and lactation. Dopamine is more associated with reward and motivation than happiness and mood. (WebMD)

Adrenaline, or epinephrine (C9H13NO3), is a hormone released from the adrenal glands, which sit atop your kidneys. During situations perceived as stressful, the hypothalamus in the brain sends chemical signals to the pituitary, also in the brain, which releases hormones into the bloodstream, triggering the adrenal glands. Adrenaline increases your heart rate, blood pressure, and blood sugar, and opens your airways—all to give your brain and body more energy and oxygen to deal with the situation, which can be exciting or dangerous. (Health Direct-Australia)

GABA, or gamma-aminobutyric acid, is a neurotransmitter that blocks nerve impulses in the brain, which has a calming or relaxing effect on the nervous system. It can be taken as a supplement to improve mood and sleep, relieve anxiety, lower blood pressure, help with premenstrual syndrome, and treat attention deficit hyperactivity disorder (ADHD). (WebMD)

Endorphins, which come in more than 20 different varieties, are also released by the hypothalamus and pituitary, usually when the body experiences pain, physical stress, or exertion. They are a form of opiate that the body produces internally to relieve pain and improve mood. (Cleveland Clinic)

Oxytocin (C43H66N12O12S2), sometimes called the “love hormone,” is also produced in the hypothalamus and released by the pituitary gland. Aside from managing aspects of the female and male reproductive systems, oxytocin is a chemical messenger with a role in behavior and social interactions, including recognition, trust, sexual arousal, romantic attachment, and parent-infant bonding. (Cleveland Clinic )

So, yes, in many ways the human brain functions like a computer system. We take in sensory information: visual images, auditory impulses, chemicals interpreted by receptors in the mouth and nose, temperature and pressure registered by sensors in the skin, and gravity’s pull interpreted by equilibrium in the inner ear. We process these signals at a conscious and subconscious level, creating and manipulating symbols related to the signals and to the abstractions that follow on them, forming interpretations and storing them as memories, triggering muscles in response to our thoughts, and coordinating internal organs to perform our bodily functions. The distributed processing system of a large industrial plant or a sophisticated robot can do as much.

But layered on these information processing systems are chemical processes that are not always under our control.1 They tell us where to focus, what to seek out, what to remember, and what to ignore. They give us attitudes about the information our brains are processing. They give us the basis of feelings about what is going on. Sometimes our feelings can be reasoned out—usually after the fact—but the feelings themselves exist separate from the information. They are a response to the information.2

So far, in the world of computers, I don’t see any parallels to this bathing of the brain in reactionary chemicals. The artificial intelligences seek out patterns and probabilities. They may have specific instructions as to which patterns are associated with a particular input prompt or a probability interpreted from the sea of data upon which the machine has been trained. But no parallel system tells them to like or feel pleasure about a particular pattern, to follow and remember it, or to reject and avoid it. The computer is still a stimulus-and-response mechanism without an allegiance or a hunch guiding the process.

I’m sorry, Mr. Spock. Pure logic is not the highest form of human mentation. Above it, and moderating it, is the universe of chemical prompts that direct our attention, our feelings, and our responses to the stimuli.

1. “Not under our control” means that a certain pattern of neural circuitry triggers a chemical response, and that pattern is either written by our genes or created from previous experience.

2. It’s interesting that almost all of these substances have a positive effect: increase attention and focus, offer reward, soothe pain, create the attachments of love. Their lack is what causes depression, anxiety, stress, loss of focus, and perhaps also loss of affection. Apparently, the brain is a positive-feedback system, and only when it goes out of balance do the negative effects appear. Carrots, not sticks.