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The universe is big, but this is the mother of all understatements. There are really no words to describe how mind bogglingly huge the universe is. It is beyond mammoth, cyclopean, gargantuan, colossal, titanic, monumental, and Brobdingnagian all put together. How immensely ginormous and humongously gigantic and vast the universe is may well be beyond the ability of our minds to understand. Consider that unit of measurement, the mile. The moon is 238,900 miles away from Earth, and we regard placing a man on the moon as one of the greatest technological feats in the history of humanity. But astronomers don’t use miles to measure distances in the universe, they use light years. The distance light travels in one year, a light year, is 5.88 trillion miles. So by this token, placing a man on the moon, which is 1.25 light seconds away from the Earth, doesn’t sound very impressive. However, it gets worse (much worse). Pluto, the furthest planet (yes, I maintain it’s a planet!) is 5.5 light hours away from Earth. The NASA New Horizons probe travelling at 36,400 miles per hour took 9.5 years to reach Pluto! Another probe, the Voyager 1 probe, is the furthest object that humanity has sent into space. Voyager 1 was launched 45 years ago in 1977, and is currently travelling at 35,000 miles per hour. The probe has so far covered 14.5 billion miles, which is 21.6 light hours. To put in perspective this “achievement”, just consider that the nearest star to Earth, Alpha Centauri is 4.24 light years away! But it gets worse (much, much, worse). Our sun is one of the stars in a spiral galaxy called the Milky Way. The Milky Way has several arms, and our sun is located in a minor arm of the galaxy about 28,000 light years from the galactic center. Within 12.5 light years of our sun, there are 33 stars. Within 250 light years of our sun, there are 260,000 stars. And within 5,000 light years of our sun, there are 600 million stars. All in all, the Milky Way galaxy contains a total of 200 billion stars and as many planets, and is roughly 100,000 light years across. The Milky Way, in turn, is surrounded by a number of the so call “dwarf galaxies” that orbit around it within a distance of 500,000 light years. Each of these dwarf galaxies contain only a few tens of millions of stars and take billions of years to orbit the Milky Way. Did I mention it gets much worse (much, much, much, worse)? Galaxies associate themselves into groups of galaxies. The Milky Way is part of a group of galaxies called the Local Group which is made up of the Milky Way and two other large galaxies, Andromeda and the Triangulum galaxy, along with their entourage of dwarf galaxies. The Local Group of galaxies spans a distance of 5 million light years and encompasses 80 galaxies and 700 billion stars. But it gets…yes, you got it. Groups of galaxies tend to associate into clusters of galaxies which in turn associate into superclusters of galaxies. The Local Group of galaxies is part of the Virgo Supercluster of galaxies which contains 100 galaxy groups and clusters. The Virgo Supercluster has a diameter of 110 million light years and harbors 200 trillion individual stars. But…you know the drill. The Virgo Supercluster is but a minor lobe of an even greater supercluster of galaxies known as the Laniakea Supercluster which is made up of about 100 superclusters of galaxies containing 250,000 trillion stars and which stretches over 500 million light years. Superclusters of galaxies in turn associate gravitationally with each other to form the largest known structures in the universe which are variously called galaxy filaments, walls, or sheets. These walls, filaments, and sheets are separated from each other by large voids of space with few galaxies which gives the observable universe a honeycomb appearance. The Laniakea Supercluster forms part of a galaxy filament called the Pisces–Cetus Supercluster Complex. This galaxy filament stretches 1 billion light years across space. To get a feeling for its size, just consider that the Virgo Supercluster, which contains the Local Group of galaxies, which includes the Milky Way Galaxy, which is where our sun is, represents only 0.1% of the total mass of the Pisces–Cetus Supercluster Complex! And the Pisces–Cetus Supercluster Complex is but one filament among tens of thousands. Astronomers calculate that the universe visible from Earth is comprised of 10 million superclusters of galaxies, which are made up of 25 billion galaxy groups, which harbor 350 billion large galaxies and 7 trillion dwarf galaxies, which all together contain a total of 30 billion trillion stars! The James Webb Space Telescope has been able to peer further back into the dark abysses of spacetime than any other telescope before it. The photo below covers an area of the universe equivalent to the area occupied by a grain of sand held at an arm’s length. There are galaxies here that are billions of light years away with the furthest one being a staggering 13.5 billion light years away. And even in this photograph there are faint smudges in the background that probably represent galaxies that cannot be resolved by the optics of the telescope!  Galaxies and stars around the galaxy cluster SMACS 0723 There are simply no units of measure or descriptors of size in our language that can help the human mind to comprehend the size of the universe. I think that in order to truly be able to grasp the sheer enormous immensity of the universe, we first have to lose our minds. So I will settle for crazy. The universe is crazy big! The image of galaxy cluster SMACS 0723 is by NASA and the Space Telescope Science Institute (STScI), and is in the public domain.
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8/18/2022 Can something be False but Not Fake? Taking a Look at the Images from the James Webb Space Telescope, Geiger Counters, Your Brain, and the Amazing Realm of PerceptionRead NowMany of us are were awed by the release of the first pictures taken with the James Webb Space Telescope (JWST). The telescope’s crystal-clear images identified previously unseen galaxies, which formed just a few hundred million years after the Big Bang, giving a us a closer glimpse of the early universe. It also revealed many new instances of gravitational lensing, a phenomenon predicted by Einstein, where a strong gravitational field bends light. And it identified many stars in the process of formation enveloped in clouds of dust and gas exposed to titanic forces unleashed by galaxy collisions or the explosion of older stars.  The Cosmic Cliffs in the Eta Carinae Nebula However, not everyone was thrilled. A group of skeptics started arguing that the photos were fake, and the fact that the first photo of the JWST was unveiled by President Biden in a ceremony at the White House provided the politization element. Someone also pointed out that the name of the galaxy cluster featured in the first image, SMACS 0723 (which stands for Southern MAssive Cluster Survey), reads “SCAM” when spelled backwards. Conspiracy theories arose claiming that the fake images are a cover up and the telescope is really a spy satellite or a weapon of some sort. It also didn’t help that a scientist as a joke posted an image of a slice of a sausage and claimed that it was an image of a nearby star taken by the JWST. Additional confusion was caused by the information that the colors in the images were not the original colors (they were false colors!), and that the images underwent a lot of computer processing (manipulation, eh? nudge, nudge; wink, wink) before being released to the public. So there you have it. A presidential photo op, hidden word messages, false colors, computer generated images, fake science, and conspiracy theories. It’s déjà vu all over again! Shades of QAnon, the 2020 election lie, the 911 conspiracy, and the moon landing hoax. All this nonsense is of course, fiction. However, as it has been stated many times by many people, truth is stranger than fiction. There is a process called “transduction” where a signal of one type gets converted to a signal of another type. A classic example of this is a Geiger counter, where the signals produced by radioactivity (ionizing radiation) are converted (transduced) into sound by the sensors and electronics of the device. Radioactivity obviously does not make a sound. The sound is a false representation of the radioactivity, but this does not make the Geiger counter readings fake. This is because the sounds produced by the Geiger counter are correlated to the intensity and timing of the radioactive emissions. Thus, with the Geiger counter we can detect a phenomenon (radioactivity) that otherwise we cannot perceive with our senses. The same thing happens with the images from the JWST. The images we have seen were taken with the telescope’s infrared cameras. But the problem is that much in the same way that we can’t perceive radioactivity, we also can’t see light in the infrared range. If we were to look at an unprocessed photo generated from the data from the telescope, we would just see faint darks and greys. The infrared photos have been converted (transduced) to the visible range much in the same way that radioactivity is converted into sound by a Geiger counter. Colors have been assigned to these images in order for us to see them. So yes, the images we see are in false colors and have been processed by computers, but they are correlated to the realities that the JWST is imaging. Thus they are not fake. And in case anyone remains skeptical about this, just consider that YOU do this all the time. Say what? Yes, you, or I should probably clarify, your brain, transduces signals all the time. In other words, your brain constantly changes one type of signal into another. Let me explain. The light we see, the sound we hear, the odors we smell, the flavors we taste, and the things we touch are not sensed directly by our brains. They are sensed by receptors at the level of our eyes, ears, nose, tongue, and skin. These receptors then proceed to convert (transduce) these light, sound, odor, flavor, and touch signals into electrical signals. These electrical signals then travel to the brain through specialized structures in neurons called axons, and millions of these axons make up the cables that we call nerves. So when we are exposed to light, sound, odors, flavors, and things we touch, what the brain perceives is shown in the figure below.  Those spikes in the image represent the electrical signals travelling down the axon of a neuron in time (the horizontal axis). This is the reality that the brain perceives. Not light, sound, odors, flavors, or the things we touch, but rather millions of these electrical signals arriving to it every second. Now, do these signals make any sense to you? Of course not! The signals have to be transduced. The brain does something similar to what the Geiger counter does or what scientists working with the JWST do. The brain processes the electrical signals coming from our eyes, ears nose, tongue, and skin and generates the sensations of sight, sound, smell, taste, and touch. These sensations are as false as the sound made by the Geiger counter or the color representations in the images of the JWST, but they are not fake in the sense that they are correlated to reality. So, for example, we cannot see the wavelength of the light that impacts our eyes, but our brain associates the wavelength of the light with colors in such a way that we perceive light of short wavelength as purple and light of long wavelength as red. This association of false brain-generated sensations with the realities around us also takes place for the senses of sound, smell, taste, and touch. So to wrap it up, what you see, hear, smell, taste, and touch is false, just like the sounds a Geiger counter makes or the color of the images of the JWST, but not fake, because these things are all correlated to reality. Welcome to the amazing realm of perception! The image of the trains of electrical impulses belongs to the author and can only be used with permission. The image of the Cosmic Cliffs, a star-forming region of the Carina Nebula (NGC 3324), is by NASA and the Space Telescope Science Institute (STScI), and is in the public domain.  A while ago I saw a documentary entitled Murder Among the Mormons. The documentary is about the exploits of the accomplished forger Mark Homann who created many seemingly old documents that were able to fool even seasoned experts. Some of these documents seemed to shed light into the early days of the Mormon Church creating conflicts with church teachings. Eventually Homann’s schemes unraveled when he accepted money for forgeries he could not deliver fast enough while living a lifestyle beyond his means. In 1985, overburdened by creditors, he looked for a way out by resorting to a bizarre scheme where he planted bombs which killed a couple of people and wounded him too.
One of the things that caught my attention about the documentary was something that Homann did in his early teens. He had developed a technique for forging mint marks on coins, and he sent one such forged coin to the treasury department for evaluation. The department evaluated the coin and let him know that it was genuine! This for him was an epiphany that pretty much set him on his life as a counterfeiter. He reasoned that if the experts declared something to be true, then for all practical purposes, it becomes true. Thus, he also reasoned, he cheated no one when he sold a forgery, as long as the experts declared it to be true. Later on, he also came to understand the power of belief in determining truth. People are unwilling to give up their beliefs, especially if the acquisition of those beliefs has involved personal sacrifice. Thus, if the experts or leaders whom the people trust say it’s true, and if people believe it is true, then IT IS true. Facts and evidence become irrelevant. Beliefs generate their own reality, and as long as people keep living by their beliefs, this is the reality that matters. We may tend to see this as a cynical view of life. We may reason that this is the sort of thing that only a sick mind like Homann’s, capable of deceit and murder, would come up with. Sadly, however, in my opinion this view of reality is often true. Homann may have been a criminal, but he was highly intelligent and talented. He grasped an important aspect of how the world works, and he used it to his advantage. If you want a more general example of what I’ve outlined in the previous paragraph, look no further than the economic meltdown that occurred during the financial crisis triggered by the housing bubble in 2007-2008. Rating agencies were assigning excellent ratings to bundles of high-risk mortgages (mortgage-backed securities) that were all but guaranteed to default. Investors and bankers nevertheless trusted these ratings and poured a lot of money into the housing market which shot through the roof. The rating agencies declared the mortgage-backed securities to be sound, investors believed them and bought the securities, and the US economy nearly went to Hades. So what am I getting at here? Science is a highly technical and complex subject that is often only accessible to the experts. Average people, and even scientists in other fields, most of the time do not have the knowledge and training to figure out what is true or not within a given complex field. This is why we often rely on the word of the experts when accepting science. But with people questioning the safety or efficacy of vaccines, the severity of the COVID-19 pandemic, the efficacy of masks and other mitigation measures, the reality of global warming, or the accuracy of evolution, what is a non-scientist to do? Do we trust what the naysayers are saying about science, or do we trust the experts? However, if we trust the experts, how do we know that we won’t end up like the persons who bought Homann’s forgeries or like the investors who bought faulty mortgage-backed securities? There are certainly no guarantees. Yes, experts can be fooled, or they can even be dishonest, but here it must be pointed out that while Homann fooled many experts, he didn’t fool all of them. Some experts eventually detected his forgeries and sounded the alarm. Similarly, several savvy investors figured out that the edifice of the mortgage-backed securities was nothing but a house of cards, and even regular folk who didn’t know enough about the matter figured out that all the crazy mortgages that were being offered could not lead to anything good. All I can tell you is that science nowadays is a diverse endeavor. The scientists involved in research live in many countries and are funded by different funding agencies. And these scientists who have different beliefs, ways of thinking, life histories, and opinions get together at meetings, present their work, vent out their disagreements in public, and publish their results in peer-reviewed journals. There are bloggers, science writers, and journalists who follow what scientists are arguing about and cover the dissenting or skeptical views. Of course, there are dishonest scientists, and there are attempts to influence the scientific process ranging from the political to the corporate. But at the same time there are organizations, watchdog groups, and individuals who are on the lookout for these dishonest people and influences. This diversity and openness make it less likely that a “cabal” of dishonest experts will mislead the public about a key issue. My advice is to listen to the experts, but keep up with the scientific debate regarding the issues that interest you. Review what the critics have to say and what the experts reply to them. Read what others including factcheckers have to say about the debate. Above all look for reputable individuals that communicate their opinions in a sober fashion in respected media outlets and avoid those people making sweeping sensationalistic claims alluding to vast unsupported conspiracy theories in media outlets notorious for pushing these claims. Image by Nick Youngson taken from Picpedia.org is used here under a CC BY-SA 3.0 license. |
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