Einstein’s Physics Crumbling Like An Old Building
If he had stuck with the Machian approach, Einstein might have attained the all-encompassing “theory of everything” that consumed the last decades of his life. He might have produced a version of his theory of gravity that would not conflict so fundamentally with quantum mechanics,” Barbour notes. But Einstein had lost his nerve.
- Zeeya Merali, in “Gravity off the Grid,” Discover, March 2012
Never has science been so devoted to praising a physicist as it has been over the past half century with Albert Einstein. Science’s love affair with Einstein was so pervasive that his philosophical thoughts about life were embraced as if heaven sent.
“e=mc2” may be quoted these days by everyone from school children to factory workers.
As everyone knows, “e” refers to energy, “m” to mass and “c” to the cosmological constant. That constant happens to be the same as the speed of light (in case we have trouble remembering, 186,000 miles per second or 300,000 kilometres per second). It was so easy to remember, only hard if you actually had to do the math for any calculation.
Here’s the catch. Light does not travel at exactly the same speed all the time. Therefore, the “constant” is not constant. Well, bear with me.
Who cares? The Bare Naked Ladies likely won’t change the lyrics of their song that is the theme for the TV series “The Big Bang Theory.” “Nearly 14 billion years ago” might not be accurate any more, but viewers will still keep watching as it’s (arguably) the best sitcom ever.
When Einstein devised his theories (special theory of relativity published first, then general theory of relativity) most people thought that space had nothing in it. It was even called a “vacuum.” The “ether” that was once considered to be out there, that accounted for the odd movement of planets in the earth-centred Newtonian universe, was more imagination than reality.
There was nothing out there, supposedly, between the planets and stars. But that didn’t work with the physics. Einstein’s theories wouldn’t work in nothingness. Then someone figured there must be dust from the original Big Bang, and neutrinos charging around as well. Still not enough.
Einstein must be right, so along came Dark Matter to patch up the theory. Still not enough. Cosmologists calculated that the universe is expanding at an accelerating rate, which didn’t fit with the theory. Let’s throw in Dark Energy. With the matter science knows exists, plug in Dark Matter, that left Dark Energy to make up 85 percent or more of the rest of the known universe, so that Einstein’s theory would work.
After all, as almost everyone agreed, Einstein was a genius--indeed “Einstein” and “genius” came to be synonyms--so any amount of creative imagination to make his theory work must be acceptable. Science hates it when religions tell people to “have faith” but it happily asked the same of people for its creations of imagination so that Einstein could continue to be the ideal of genius.
Here’s where it gets messy. Einstein’s theories depended on a fourth dimension, called space-time. Light--part of the “constant” remember--bends around large objects, just as river water bends around rocks in its way. Does light have to speed up to make up the extra distance required to divert around large objects, or does it slow down, thus throwing off calculations?
Time, as Einstein told us, is flexible. In relatively empty space, it speeds up, whereas in denser stuff such as galaxies it slows down. If light (the constant) travels at 186,000 miles per second and the length of a second can change depending on where it is being measured, what can be constant about the constant?
How accurate is the widely accepted belief that our universe is 13.7 billion years away from the Big Bang? That number was calculated based on the rate that supernovas great distances away were moving. The light from those supernovas bent around galaxies and changed speed as it travelled through larger ones. These were not considered in the calculations.
David Wiltshire, a New Zealand physicist at the University of Canterbury, claims that if the age of the universe were calculated based on light travelling through empty space, the age would be 18 billion years. If the light travelled at the speed it does passing through galaxies, the age would be 15 billion years.
Wiltshire’s “older” universe age results from his beginning from a different set of physical assumptions than those physicists who calculate it at 13.7 billion years.
Assumptions, you say? Exactly. Physical calculations change depending on which set of assumptions you begin with. What then should we believe?
To make things more awkward for Einstein’s legacy, CERN, the European Space Agency’s huge facility for studying super particles, recently reported that it had timed neutrinos travelling faster than light, a phenomenon that does not fit with Albert’s theories. While a few scientists search diligently for weaknesses in the CERN report, there is no doubt that many are still trying to find a way to travel faster than light. Like many other scientific marvels that came out of the original Star Trek classic TV series, time travel and faster-than-light space travel seem destined to come to pass some day.
I still believe in Albert Einstein, though his assumptions might have been inaccurate. I still believe in gravity, though no one at this point has any idea what it is or why objects attract each other--anyone who says he does is overconfident about his guess.
I am not certain what to believe about the age of our universe. Flexible time may be a problem. An undependable constant is troubling. Flexible space is still hard for me to wrap my head around.
Of one thing I have great faith. My wife has just called me to say that supper is ready and if I try to stretch time too much before completing this writing, my supper will be cold. I have confidence in that constant.
Bill Allin is the author of Turning It Around: Causes and Cures for Today’s Epidemic Social Problems, a book of big but simple ideas about how to change the material taught in our schools so we can all live longer, healthier and safer lives.
Learn more at http://billallin.com
Showing posts with label gravity. Show all posts
Showing posts with label gravity. Show all posts
Thursday, May 10, 2012
Monday, June 07, 2010
It's About Time: What You Don't Know But Should
It's About Time: What You Don't Know But Should
Humans invented the concept of time. It didn't exist, in the way we know time, before we came along. No other creatures on the planet have the same concept of time as we do. Or, if it did exist, who would know?
Is time real or imaginary? Einstein considered it real, counted it as a component of what he called the fourth dimension, space-time. Space-time figured prominently in projections based on his theory of relativity.
But so did gravity and some physicists (albeit far from a majority) wonder now if gravity is everything Einstein says it is. For example, where is all that Dark Matter that supposedly comprises far more of the universe than the matter we can detect? For that matter (excuse the pun, I couldn't resist), where is all the "real" matter that should exist but we're having difficulty finding since we became aware of the Big Bang and developed big telescopes? University of Maryland astronomer Stacy McGaugh's study shows that many galaxies have much less matter than should be there to account for their gravitational pull.
If gravity is not what Einstein said it is, then that messes up our concept of time. So does the average U.S. city commuter really lose 38 hours a year to traffic delays or is that just imagined? The answer (you're not going to like this, I didn't) is that most of what we believe about our lives is based on how we perceive it (what we imagine it to be) more than on reality. (Okay, I wouldn't have time to explain that even if I could.)
After nearly a century of using Daylight Saving Time (DST), we still aren't sure why we use it. Benjamin Franklin introduced it as a joke. He said that if we got up an hour earlier each morning we could get an hour's more work done in daylight and save candles in the evening. The U.K. adopted DST in 1917, most of the rest of the world followed. (Personally, I can't see sleeping through daylight in the early morning hours in summer when that's often the best time to work outside. The mosquitoes in our area agree.)
Daylight Saving Time accounts for a drop in electricity use. The U.S. Department of Energy claims power demand drops by 0.5 percent during DST, saving three million barrels of oil in the U.S. alone.
By the way, it's not Daylight Savings Time. It's Saving. Savings is an account you have at the bank. That is, you would if you had any money to keep in it.
One study watched how quickly bank tellers made change, pedestrians walked and mail clerks spoke and concluded that the fastest paced U.S. cities are Boston, Buffalo and New York. (As an aside, I have often wondered if rats are insulted when we refer to the fast paced life of humans in cities as the Rat Race. If so, they had better get over it because half the population of the world lives in cities today, most in big cities.)
The psychologist who did that study found the slowest paced cities were Shreveport, Sacramento and Los Angeles. (Nothing in the report about the pace of life of rats in those cities.)
Back in the old days one second used to be defined as 1/86,400 the length of a day. (We'll pause here while you fetch your calculator if you like.) A second can still be defined that way, but it will be a longer second. The friction of tides as a result of gravity by the sun and moon slow earth's travel, lengthening our day by three milliseconds each century. (Feel free to think of it as "mutual attraction" not gravity if my previous statements made you uncomfortable with that word.)
Let's put that into perspective. In the time of the dinosaurs the day was only 23 of our hours long. (You don't suppose they had a dinosaur version of Rodent Race that caused the dinos to die off.)
Speaking of things that slow earth's rotation, even the weather can do it. El Niño winds can cause earth's rotation to slow by a fraction of a millisecond over just 24 hours.
Technology can do better than that. In 1972 atomic clocks in more than 50 countries were made the final authority on matters of time. They're so accurate that they lose about a second in 31.7 million years. But in 31.7 million years our day will be a half hour longer, so won't all our atomic clocks be wrong?
Actually, no. To keep the clocks in synch with earth's rotation we now add a "leap second" every few years. The most recent leap second was added this past New Year's Eve. (I thought 2009 seemed longer for some reason.)
One clock does even better than the network of atomic clocks. The clock at the National Institute of Standards and Technology, in Boulder, Colorado, measures the vibrations of a single atom of Mercury and is accurate to less than one second of loss in one billion years. (Who knew an atom of mercury could shiver that long?)
We think of timekeeping as standard now. In fact we call it Standard Time. Until the age of trains that had to meet set schedules in the 1800s, every village had its own version of standard time. They used solar noon in their respective areas. As odd as it seems now, a few watches were made in those days of confused standard times for trains that kept track of two times, one the local standard time and the other "railway time."
The U.K. adopted Standard Time first through an act of Parliament. The U.S. came on board on November 18, 1883. Some people speculate that the adoption of Standard Time may have prompted Einstein to think about how space and time might be united in his theory of relativity.
Einstein said that gravity affects the passage of time. So a passenger in an airplane, flying where gravity is weaker, would age a few nanoseconds more than a person who kept his feet on the ground.
Quantum theory claims that the shortest possible period of time (known as Planck time after the German physicist whose work began the whole study of quantum theory) is 0.0000000000000000000000000000000000000000001 second.
Most scientists today believe that time as we know it began with the Big Bang, created with the rest of the universe 13.7 billion years ago. If you care, stay tuned because that belief could change any time now.
Will time ever end? Three Spanish scientists claim it will. They say our expanding universe is not really expanding at all. Rather time is slowing down, making it seem to us as if the universe is expanding. According to their calculations, time will eventually stop, at which point everything we know will stop as well. (I was going to calculate when that would be, but I don't have time.)
Bill Allin is the author of Turning It Around: Causes and Cures for Today's Epidemic Social Problems, a guidebook for teachers and parents who want their children to develop all aspects of their lives at the right time.
Learn more at http://billallin.com/
[Primary source: Discover, March 2009]
Humans invented the concept of time. It didn't exist, in the way we know time, before we came along. No other creatures on the planet have the same concept of time as we do. Or, if it did exist, who would know?
Is time real or imaginary? Einstein considered it real, counted it as a component of what he called the fourth dimension, space-time. Space-time figured prominently in projections based on his theory of relativity.
But so did gravity and some physicists (albeit far from a majority) wonder now if gravity is everything Einstein says it is. For example, where is all that Dark Matter that supposedly comprises far more of the universe than the matter we can detect? For that matter (excuse the pun, I couldn't resist), where is all the "real" matter that should exist but we're having difficulty finding since we became aware of the Big Bang and developed big telescopes? University of Maryland astronomer Stacy McGaugh's study shows that many galaxies have much less matter than should be there to account for their gravitational pull.
If gravity is not what Einstein said it is, then that messes up our concept of time. So does the average U.S. city commuter really lose 38 hours a year to traffic delays or is that just imagined? The answer (you're not going to like this, I didn't) is that most of what we believe about our lives is based on how we perceive it (what we imagine it to be) more than on reality. (Okay, I wouldn't have time to explain that even if I could.)
After nearly a century of using Daylight Saving Time (DST), we still aren't sure why we use it. Benjamin Franklin introduced it as a joke. He said that if we got up an hour earlier each morning we could get an hour's more work done in daylight and save candles in the evening. The U.K. adopted DST in 1917, most of the rest of the world followed. (Personally, I can't see sleeping through daylight in the early morning hours in summer when that's often the best time to work outside. The mosquitoes in our area agree.)
Daylight Saving Time accounts for a drop in electricity use. The U.S. Department of Energy claims power demand drops by 0.5 percent during DST, saving three million barrels of oil in the U.S. alone.
By the way, it's not Daylight Savings Time. It's Saving. Savings is an account you have at the bank. That is, you would if you had any money to keep in it.
One study watched how quickly bank tellers made change, pedestrians walked and mail clerks spoke and concluded that the fastest paced U.S. cities are Boston, Buffalo and New York. (As an aside, I have often wondered if rats are insulted when we refer to the fast paced life of humans in cities as the Rat Race. If so, they had better get over it because half the population of the world lives in cities today, most in big cities.)
The psychologist who did that study found the slowest paced cities were Shreveport, Sacramento and Los Angeles. (Nothing in the report about the pace of life of rats in those cities.)
Back in the old days one second used to be defined as 1/86,400 the length of a day. (We'll pause here while you fetch your calculator if you like.) A second can still be defined that way, but it will be a longer second. The friction of tides as a result of gravity by the sun and moon slow earth's travel, lengthening our day by three milliseconds each century. (Feel free to think of it as "mutual attraction" not gravity if my previous statements made you uncomfortable with that word.)
Let's put that into perspective. In the time of the dinosaurs the day was only 23 of our hours long. (You don't suppose they had a dinosaur version of Rodent Race that caused the dinos to die off.)
Speaking of things that slow earth's rotation, even the weather can do it. El Niño winds can cause earth's rotation to slow by a fraction of a millisecond over just 24 hours.
Technology can do better than that. In 1972 atomic clocks in more than 50 countries were made the final authority on matters of time. They're so accurate that they lose about a second in 31.7 million years. But in 31.7 million years our day will be a half hour longer, so won't all our atomic clocks be wrong?
Actually, no. To keep the clocks in synch with earth's rotation we now add a "leap second" every few years. The most recent leap second was added this past New Year's Eve. (I thought 2009 seemed longer for some reason.)
One clock does even better than the network of atomic clocks. The clock at the National Institute of Standards and Technology, in Boulder, Colorado, measures the vibrations of a single atom of Mercury and is accurate to less than one second of loss in one billion years. (Who knew an atom of mercury could shiver that long?)
We think of timekeeping as standard now. In fact we call it Standard Time. Until the age of trains that had to meet set schedules in the 1800s, every village had its own version of standard time. They used solar noon in their respective areas. As odd as it seems now, a few watches were made in those days of confused standard times for trains that kept track of two times, one the local standard time and the other "railway time."
The U.K. adopted Standard Time first through an act of Parliament. The U.S. came on board on November 18, 1883. Some people speculate that the adoption of Standard Time may have prompted Einstein to think about how space and time might be united in his theory of relativity.
Einstein said that gravity affects the passage of time. So a passenger in an airplane, flying where gravity is weaker, would age a few nanoseconds more than a person who kept his feet on the ground.
Quantum theory claims that the shortest possible period of time (known as Planck time after the German physicist whose work began the whole study of quantum theory) is 0.0000000000000000000000000000000000000000001 second.
Most scientists today believe that time as we know it began with the Big Bang, created with the rest of the universe 13.7 billion years ago. If you care, stay tuned because that belief could change any time now.
Will time ever end? Three Spanish scientists claim it will. They say our expanding universe is not really expanding at all. Rather time is slowing down, making it seem to us as if the universe is expanding. According to their calculations, time will eventually stop, at which point everything we know will stop as well. (I was going to calculate when that would be, but I don't have time.)
Bill Allin is the author of Turning It Around: Causes and Cures for Today's Epidemic Social Problems, a guidebook for teachers and parents who want their children to develop all aspects of their lives at the right time.
Learn more at http://billallin.com/
[Primary source: Discover, March 2009]
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