In the 2010’s, science seems to produce miracles every day.  We are constantly enthralled by ever-changing smart phones and life-saving medicines.  Yet one of this decade’s most important science stories is something that didn’t have much media reach – the direct detection of gravitational waves.  This post will explain what gravitational waves are, how they were recently detected, and what this means for the sake of science.

What are gravitational waves?

A boat sitting on a lake displaces (pushes aside) some of the water.  As the boat moves, the displacement of water follows it.  The disturbance in the water then propagates outward from the boat in waves.   Physicists predicted a century ago that gravity can behave in a similar way.  A massive body like a star warps space-time, especially in its vicinity.  When the star is disturbed in certain ways, the space-time warp radiates outward from the star in gravitational waves, carrying energy with it.  If the star is massive enough and particularly agitated, the waves could even be detected from Earth.    

How do we know this?

Our best understanding of gravity today is Einstein’s general theory of relativity (GR).  His theory gave physicists much to think about, as it was a degree more refined and explanatory than Newton’s 17^th century model of “action at a distance”.  When Einstein published this theory in 1915, however, it was mostly theoretical.  It made good sense to those (few) who understood it, and it went a long way toward explaining how the universe works on a large scale.  Believers were eager to see if relativity were really supported by astronomical observations.  There were a few early corroborations.  GR immediately explained anomalies in Mercury’s orbit that made no sense otherwise.  Astronomers knew that if Einstein were right about gravity as the warping of space-time, light rays from distant stars should be bent as they passed near the sun, slightly shifting the stars’ locations in the sky.  That can only be observed during a total solar eclipse.  The opportunity came in 1919, and during that eclipse stars near the sun did in fact appear slightly offset from their true positions.  Since then, distant galaxies have been observed acting as “gravitational lenses”, making galaxies directly behind them appear as rings of light rather than points!

Einstein was not perfect.  His model of GR was based on the assumption that the large-scale universe was static.  When it became clear that the universe is actually expanding, he had to modify his equations to suit observational reality.  Thus, even the best ideas from the smartest people cannot be taken as gospel.  They have to be borne out by reality.       

Over the decades, all of Einstein’s predictions were directly confirmed, except one – gravitational waves.  There was actually good indirect evidence dating back to the 1970s.  Binary black holes were seen spiraling in toward one another, gradually losing energy.  That observation was consistent with the idea that they were transmitting gravitational energy out into space.  Still, the next logical step in nailing down general relativity was detecting those waves and studying them. 

Gravitational Wave Detection

A gravitational wave causes periodic stretches and compressions of space.  If such a wave were headed straight toward you right now, it would cause space in your vicinity to stretch horizontally while compressing vertically, and then to stretch vertically while compressing horizontally, in a continued cycle.  To detect these fluctuations, scientists shine lasers in two perpendicular directions, essentially vertical and horizontal.  The lasers travel equal distances until they each strike a mirror and get reflected back to meet each other in the middle.  They are polarized so that, on a normal day, they cancel each other out at this middle point.  But if a gravity wave passes by, one laser beam gets longer while the other one gets shorter, and then they no longer quite cancel in the middle!  Any residual light patterns are recorded, producing a trace of the gravitational wave.   

The problem is that gravitational waves are difficult (frankly, all but impossible) to detect.  They are only generated by extreme systems like binary black holes.  There aren’t many of those within a billion light years.  By the time those waves reach us, they are inconceivably small.  A typical gravity wave is described mathematically as having dimensionless strain amplitude of 10^-20.  This means that a distance of 10²⁰ centimeters (from here to a typical star in the night sky) gets distorted by only 1 centimeter (the width of your pinky finger)!  How on Earth (literally) can we detect that?! 

The secret lies in engineering that is just as incredible as the science of relativity.  Fortunately, the lasers don’t have to shift very much to produce an interference pattern.  Mirrors are used to lengthen the lasers’ paths, thus lengthening their stretches and compressions.  The real challenge is separating out these miniscule oscillations from normal everyday movement; gravitational waves are much smaller than disturbances in the laboratory such as footsteps or even air currents.  Engineers have found workarounds.  The mirrors are suspended from four levels of pulleys, each of which dampens movement by orders of magnitude.  The whole system is controlled by advanced “noise reduction” technology.  If a truck passes by outside, the control system creates its own minor vibrations to cancel out the truck’s!  Finally, the results from one gravitational-wave observatory are checked against another one elsewhere in the world.  All these steps ensure that the equipment is not falsely reading local jostles as cosmological events. ¹

A handful of gravity wave detectors such as the Laser Interferometer Gravitational-Wave Observatory (LIGO) have been in operation since the 1990s.  They produced absolutely no results for two decades.  As a Caltech alumnus, I was long aware of and curious about the LIGO, which is a Caltech lab in conjunction with MIT and the NSF.  After some key engineering improvements in 2015, LIGO finally made a breakthrough and detected gravitational waves.  In fact, it almost immediately detected waves from three different events.  Go Caltech!  The most recent detection was just announced in June, 2017. 

Can we see or hear gravitational wave events?

Well … yes and no. 

The gravitational waves detected so far were all caused by the same phenomenon, called a black-hole in-spiral.  A pair of black holes in very close, very fast orbits around each other spiral inward for a collision.  The forces behind a system like that are impossible to imagine.  Picture two large stars, each ten times more massive than the sun.  Then shrink each star down to the size of a baseball.  As they orbit each other, they radiate energy away in gravitational waves, causing them to inch closer toward their mutual center.  After millions of years, their small size permits them to get within a few kilometers of one another.  Like an ice skater pulling in her arms, their angular momentum causes them to spin faster and faster until they are twirling at ludicrous rates, stirring the very space around them.  The gravitational waves reach a climax as the two black holes merge into one.  Only the peak of this wave is detectable on Earth, literally the split second of coalescence.  After that, the new larger black hole behaves in a spherically symmetrical way and becomes gravitationally quiescent. 

We cannot literally “see” such an event with telescopes, but a computer simulation of such a black hole mating – with gravitational waves emanating outward – is shown here: ² http://www.youtube.com/embed/157rfAqypcc

Just about any wave can be converted into a sound wave so we can “listen” to it.  A black-hole collision produces a powerful but brief burst of waves that is detectable for about one second.  As shown in the video, the waves increase in frequency during that second, which we would interpret as a rising pitch.  Scientists call it a “chirp”.  You can listen to the chirps of the first two detections in this video: ³

So what?

These waves are a scientific breakthrough.  For starters, they are Einstein’s final witness.  Everything he said about general relativity is now seen to be true.  We now feel that we have a very complete understanding of what gravity does (though the ultimate question of why mass distorts space-time is still unknown). 

The first gravitational wave was detected in September, 2015 and announced in February, 2016.  It’s a pretty cool coincidence that this processing period spanned the date November 25, 2015, the 100^th anniversary of publication of Einstein’s general relativity.

In addition, gravitational wave detectors bring the promise of a new generation of observatories.  Classic telescopes detect visible light.  Modern versions such as radio telescopes see outside the spectrum of the human eye, but they are still detecting variants of light, electromagnetic radiation.  Gravitational waves are completely outside the realm of electromagnetics.  They are not obscured by physical objects or dimmed by dust, so observatories such as LIGO have an unobstructed view of them wherever they occur.  They also emerge from very interesting astronomical phenomena that do not emit light.  That includes black holes, of course, and even the big bang.  The oldest electromagnetic radiation in the universe came about 100,000 years after the big bang.  Gravitational wave detectors could pierce that veil and peer indefinitely closer to the actual moment of creation.

What gravitational waves are not

The name “gravitational waves” can be a little misleading.  They are not the normal mechanism by which gravity works.  The earth goes around the sun because of the sun’s gravity, which does warp space-time in the solar system, but in a static field.  There are no gravitational waves emanating from the sun to the earth.  Waves are an exception rather than a rule in GR, simply a consequence of certain asymmetric movements. 

It is also important not to confuse gravitational waves with gravitons.  The graviton is a hypothetical construct that some theoreticians use to explain what could cause gravity in the first place (ie why mass warps space-time).  The three other forces of nature (electromagnetism, the weak nuclear interaction, and the strong nuclear force) are all transmitted by strange subatomic units called bosons, which can behave as particles or waves.  The most familiar boson is the photon, the light wave / particle.  Could it be that gravity is also transmitted by bosons?  Nobody knows.  Certainly nobody has ever detected one.  The graviton hypothesis comes at gravity from a very different direction – Einstein came at it cosmologically, on the very large scale, whereas the graviton model emerged from quantum mechanics, the study of the very small.  As for myself, I am skeptical.  Graviton theory is mathematically consistent only if it allows “hidden extra dimensions” for the gravitons to wiggle around like little strings.  It seems to be a non-falsifiable speculation.  To be clear, gravitons did not come out of Einstein’s theory of relativity.  On the other hand, GR only explains how mass warps space-time, not why.  A full understanding of gravity would have to go beyond even Einstein’s imagination. 

This September 11, I feel compelled to write a few words about the War on Terror.  It is an important issue this year as Americans make big choices.  We all know that emotional thinking can cloud judgment – and the War on Terror is one of the most emotional issues of our time.  When you look at it objectively, though, you reach a striking conclusion.  Yes, terrorists are definitely evil.  But in the grand scheme of things, they are not very deadly to Americans.  When you compare the cost of this war to its benefits, it is very hard to justify on its present terms.

American conservatives describe the War on Terror as a “Clash of Cultures”.  This characterization is an ideological belief, not a fact, and it is not productive.  A look at worldwide terrorism deaths reminds us what the fight is really about:  instability within the Moslem world.  Of the roughly 20,000 terrorist deaths worldwide in 2013, a majority of them were in Iraq or Afghanistan.  90% of them occurred in 10 African / Asian countries that are home to terrorist groups.   ¹ These groups are militias aimed at local governments or other sects.  Most of these groups don’t target outsiders.  ISIS and al Qaeda are the main exceptions.  The US and other countries engage them directly in combat, and they strike back at our civilians.

From 2001 – 2013, the number of Americans killed by terrorist attacks was about 3,000.  Outside of 9/11/01 itself, that number is about 400, and of those only 50 were on US soil. ² That was a whole decade’s worth of casualties.

By contrast, on a typical day (based on annual rates), 90 Americans are killed by guns at home or in the streets – by angry acquaintances, accidents, or suicide. ³  Another 90 Americans are killed in car accidents.  ⁴  The overwhelming majority of preventable deaths in the US – 2,000 per day – are caused by our own stupid decisions to smoke, drink, overeat, and abuse drugs. ⁵

Terrorism is not even close to our biggest problem.

Nevertheless, more than half of Americans are “very concerned about Islamic extremism.” ⁶  That’s a higher rate than in Pakistan!  This disconnect is not surprising.  People don’t think with statistics.  We think with emotions.  Lifestyle-related deaths are not as evil or terrifying as terrorist attacks.

The emotionally-driven political response has been vastly out of proportion.  This war has cost trillions of dollars ⁷ , killed perhaps a million people ⁸ (wow), and sacrificed 7,000 US soldiers in combat ⁹ to avenge our 3,000 dead.  Not only that, but ironically most of those 400 American civilian deaths since 2001 have resulted from counterattacks against our War on Terror.

This conflict means less to the US, but more to the world, than most Americans realize.  The US needs to downscale its response, make it more efficient, and share it more evenly with its allies.  Our trillions could be much better spent on intelligence, police, and security.  Better yet, the responsibility and the budget should be spread among many nations.  The global solution to the problem is a very interesting discussion, and beyond the scope of today’s post.

As for the upcoming election, the two presidential candidates, for all their mudslinging and difference in style, have roughly similar platforms on the War on Terror.  Some of the key differences include:

• Trump has expressed his desire to remove the US from NATO.  This would be counter-productive, as the solution needs to be international.  Trying to shore up the entire Moslem world would stretch America far too thin.  Then again, he has also spoken in favor of coalition support.
• HIllary Clinton wants to work with Moslem Americans as a “coalition at home”.  ¹⁰
• Clinton supports stricter gun control for people on FBI watch lists.
• Trump wants the US military to grow even larger.  Clinton supports a sustainable military with enhanced cyber capabilities.
• Trump opposes arming Syrian rebels.  Secretary Clinton supported arming them, but Obama tried that and it backfired.  She does not include arming rebels in her presidential platform.

The more serious difference between the candidates and their supporters is their outlook on the conflict.  Trump buys into the “Clash of Cultures” storyline.  He and his voters see ISIS as first and foremost out to get America.  That outlook doesn’t get us any closer to the real problems in West Asia and their solutions.  Trump is riding on the coat tails of American fear, perceiving the terrorist danger as so large that it threatens the entire nation.

FDR said, “The only thing we have to fear is fear itself.”  Yoda was just as wise when he said, “Fear is the path to the dark side.  Fear leads to anger, anger leads to hate, hate leads to suffering.”  For Americans right now, it is just as important to conquer our terror as to conquer the terrorists.

The ongoing saga of the “Iran nuclear deal” is difficult to follow for the casual news watcher.  It never seems to end.  Israelis, Saudis, and US Republicans oppose it without explaining which terms they are against, or what they would like to propose instead.  The opening of diplomatic relations with Cuba is also hotly debated.  But these are positive developments in two ways.  First, in the true spirit of a contract or treaty, the Iran nuclear deal offers something positive for both sides.  Second and more broadly, this recent trend indicates an opening of communications between geopolitical enemies.  Obama’s belief in “talking to the enemy” has been one of the most controversial elements of his presidency.  With a perspective outside of political bias, I agree that it is the right course.  Communication is healthy for international relations just as it is for personal relations.  This has already been proven by Republican presidents Nixon and Reagan.  At the very least, communication humanizes the enemy.  The US and the West should continue the policy of talking openly to its adversaries – Iran, Cuba, North Korea, and more.

The Iran Nuclear Deal in a Nutshell

Iran has a large nationwide program of uranium enrichment.  Enriched uranium can be used either for nuclear power plants or (at much higher concentrations) nuclear weapons.  Obviously, nobody would like to see Iran develop an arsenal of nuclear bombs.  Thus, the primary interest in the West is to keep Iran free of weapons-grade uranium.

To put pressure on the Iranian government – for nuclear activities and other reasons – the US has “boycotted” Iran with trade sanctions since the revolution of 1979.  The UN and EU followed with major sanctions in the 21^st century.  Other nations have imposed minor sanctions as well.  The sanctions have had their primary intended effect of making it difficult for Iran to develop nuclear weapons.  However, they have also had a major impact on Iran’s overall economy, including high inflation and a current unemployment rate of well above 20%.  After four decades, these actions directed against the Iranian government have made life very difficult for ordinary people throughout the entire country.  This is bad not only for Iran, but for perpetuating Iran’s negative perception of the outside world.

For decades, the US and Iran’s mutual strategy was to be strong-headed and hope to win a battle of wills.  The US hoped that sanctions would eventually cripple Iran to capitulation; lifting sanctions was not an option.  Iran felt that it had no choice but to arm itself into a stronger position; nuclear enrichment was non-negotiable.

Diplomatic overtures began in 2003.  Iran offered to negotiate a middle ground.  The US refused, after which Iran vastly increased its nuclear enrichment program.  A decade later, after UN and EU sanctions had strained Iran even further, a tentative agreement was reached between Iran and a multinational coalition representing the US, UN, and EU.  The gist of the agreement was very simple.  In exchange for sanctions relief, Iran would limit its uranium enrichment to peaceful purposes, and open its nuclear energy program to international monitoring.  The 2013 agreement gave Iran and its negotiators time to work out a “framework,” and then the details of execution.  A framework for such a deal was reached last week, in April, 2015.

The agreements of 2013 and 2015 are historic and significant.  This is the first time that Iran has offered any sort of concessions on its nuclear program.  The agreement-in-progress includes important provisions allowing the International Atomic Energy Agency (IAEA) to inspect Iran’s uranium industry closely.  Easing of sanctions would make life better for average Iranians.  It would also start to open the Iranian market to many importers and exporters around the world.  Until Iran proves its commitment to the deal, the most important sanctions (those related to uranium and military imports / exports) would remain in place.  In short, there would be clear benefits for the global economy and safety.  This is an important step forward.

As the deadline for the framework approached, the “nuclear deal” became hotly controversial.  Iran’s greatest regional enemies, Israel and Saudi Arabia, oppose the idea of negotiating with Iran.  They are not part of the current talks.  In the US, the Republican Party follows Israel’s lead.  Interestingly, opponents of the talks are very vague about exactly what they oppose.  Benjamin Netanyahu argues that the deal would only favor Iran, “without receiving anything tangible in return.”  He does not acknowledge the value of Iran’s changing stance, from defiance to compromise.  US Republicans complain vaguely that the deal is not tough enough, that it should insist on more enrichment curtailment while offering less sanction relief.  Essentially, what they are arguing for is a repudiation of negotiations altogether; they believe in principle that the US should continue opposing Iran with brute force instead of diplomacy.  I have not heard Republicans propose specific alternatives to any of the deal’s terms.  Keep in mind that congressional opponents are not the same people who are involved in talks.  The negotiators have had years to get to know specific Iranians, their attitudes, needs, and points of flexibility.  Third parties are expressing opposition for opposition’s sake.   Israel and Saudi Arabia’s stance is apparently, “If Iran is for it, we’re against it,” while Republicans feel, “If Obama is behind this, we won’t allow it.”  Some Republicans raise a legitimate point about which branch of government should be involved in the negotiations.  That’s for Congress and the White House to wrestle over.

Cuban Diplomacy

The relationship between the US and the Castros has always been rocky.  After Fidel Castro’s first few aggressive years in office, the US imposed a particularly strong embargo against Cuba and cut off diplomatic ties.  It can be said that this only made matters worse.  Shut off from the US, Cuba turned to the USSR for oil, money, and defense, setting the stage for the particularly bad crises of the 1960s.  Even after the USSR collapsed and Cuba went into depression, neither nation made a move to mend fences.  Talks have only resumed under Raul Castro’s administration.  A trickle of trade is now being allowed, and there is talk of reopening the embassies.  An open channel of communication could even lead to an easing of the embargo in exchange for Castro concessions.  Again, there could be something good in it for both sides.  Nevertheless, of course there is some opposition to these gestures of peace too.

Aside from some matters of asylum, political prisoners, and allying with other dictators, the Castros have not actually posed a threat to the US since at least 1980.  They have just been corrupt dictators in their own nation.  Most of the pressure to shut them out comes from two sources: Cuban-Americans who have family left behind on the island, and those who once again misunderstand the purpose of communication.

To communicate does not mean to condone.  Yes, Fidel Castro wrongfully took his country by force, seized US assets, and harbored Soviet nuclear weapons.  By all accounts, the Castros and their government never should have been in power.  But let’s face it, they are awfully entrenched there.  What are we going to do about it?  Ignoring them has not proven very effective at accomplishing anything.  The US embargo, like the sanctions against Iran, has a strong grip on Cuba.  It is obviously not squeezing the Castros out of power, and is hurting ordinary Cubans more than the government.  The UN recommends lifting it.  The embargo’s greatest value now is as a bargaining chip.  In this century, the US’s main goal is to see a Cuban transition to democracy, at least after the Castros’ death.  Maybe the best way to get Raul to listen to what the US has to say is for the US to listen to what he has to say.  It sounds like he could be willing to negotiate some democratic reforms in exchange for some economic relief.

Upshot

If a man were having serious problems with his boss, a neighbor, or his wife, most people would give the same advice:  Talk to her!  Whether it may be at the dining room table or in pre-trial litigation, at some point they need to figure out how to end the conflict without hurting each other.  That’s still true if the neighbors-at-odds are governments – even bad governments.

The alternatives to communication are recalcitrance, failure to understand each other, demonization, retribution, and violence.  Negotiation can be difficult, because it requires compromise.  But the very act of negotiation, even the willingness to negotiate, can facilitate a mutually agreeable position.  And communication does not necessarily have to mean negotiation or validation.  Formal discussions force each side to identify specific points of contention, rather than reacting emotionally to each other.

Iran is willing to cap enrichment and open its nuclear industry to inspection.  That’s worth an easing of sanctions.  The Castros have not threatened the US in decades, and they are willing to normalize relations.  That’s worth meeting them in the middle.  I think we’d all prefer to have international seats at the table when discussing a post-Castro Cuba.

Today, CBS will be broadcasting a rare reunion of Paul McCartney and Ringo Starr, on the occasion of their 50th anniversary in America.  The concert was filmed the day after the Grammies, just a couple of miles from me here in LA.  The occasion is also marked by several magazine cover stories this month.

The Beatles were a phenomenon that will not happen again, a band that was both the most popular and the best.  They made their US debut in 1964, when TV was still a relatively new medium and the number of channels was very limited.  The national dialogue was narrowly focused.  Today, we enjoy much greater diversity in entertainment options, but at the cost of being fragmented.  There is no turning back to a time when one band can catch the attention of children and adults in one monolithic nationwide audience.

The Beatles are usually remembered for their popularity and timeliness.  They wrote catchy songs, and they were right there at the leading edge of baby-boomer youth culture.  The 1960s was a decade of enormous social changes, and will probably merit a section all its own when I write Chapter 2.  It was really the beginning of of what we would identify with as “today’s world.”  As a cultural phenomenon, The Beatles were indelibly impressed on the social fabric of the times.  Beatlemania is a necessary ingredient of nostalgia for that period of time.  Even I have always felt oddly retro-nostalgic for the decade before I was born, when I hear the Beatles songs that still dominated the airwaves in my first few years.  And to think, the Beatles almost didn’t make it onto the Ed Sullivan show.  Management had trouble finding a sponsor.  Bayer aspirin came through at the last minute.  Isn’t it interesting how entertainment and pragmatic economics are intertwined.  Ultimately, the Beatles got on TV in February, 1964 because Bayer needed to sell aspirins.

Even aside from their cultural signficance, all music nerds will agree that The Beatles were a game-changer in the art.  It’s a little ironic that they started out as a cover band, and actually came to the game kind of late for rock-and-roll.  Many music agents at the time felt convinced that “guitar based bands” were already on their way out in 1962, as the Beatles sought their first record deals.  Their catalog from 1962 – 1964 is usually played on the same radio stations that play the “oldies” of the 1950s.

From the start, though, one thing was unique:  The Beatles synthesized all of the rock-n-roll roles into one band.  Before that time, the industry had specialists.  There were songwriters (Willy Dixon, Neal Sedaka).  There were great vocalists (Roy Orbison) and vocal groups (The 4 Seasons).  There were instrumentalists (Chuck Berry, Jerry Lee Lewis).  There were stars (Elvis).  Very few had it all in one package.  With a few concurrent exceptions like the Rolling Stones and The Beach Boys, the Beatles were the first self-contained rock band.  Their Ed Sullivan appearance set the new industry standard.  After that, it was commonly understood that bands should be able to write their own songs and perform them with panache.  It was an extremely high bar.  Honestly, in the whole history of rock music, only maybe a few hundred bands have ever been capable of pulling it off well.

But it was the next year, 1965, that the Beatles started to metamorphose and to take the art of music in new directions.  That was the year that the Beatles became the first progressive rock band, with a focus on studio production.  They launched two albums, “Help” and “Rubber Soul.”  These included songs the likes of which had not been heard before, such as “Ticket to Ride,” “Yesterday,” “Michelle,” “Norwegian Wood,” and “In My Life.”  1965 was a watershed year for the Beatles and other artists.  The Kinks’ “You Really Got Me” brought distortion to the electric guitar while McCartney introduced fuzz bass.  It was the year of “Satisfaction” and “California Dreaming.”  Then the scene exploded.  Psychedelia appeared in 1966, again with Beatles contributions.  Hard rock / heavy metal was appearing by the late ’60s, influenced by Beatles songs like “Helter Skelter” (1968) and “She’s So Heavy” (1969, the year before Black Sabbath’s first album).  Even the bands that are usually given credit for inventing progressive rock, such as Pink Floyd and King Crimson, made their debuts only after the Beatles mid-career mark.  The Beatles continued to adapt their sound and be at the forefront of songwriting and production until their last album, “Let It Be,” in 1970.  They went out on top.

It is no exaggeration to say that the entire era of classic rock music was just three decades of Beatlemania.  The scene remained rich until the early ’90s.  I regard Dream Theater’s 1992 “Images and Words” as the last significant classic rock album.  It was preceded in 1991 by the sudden explosion of modern rock, a scene that produced great albums for only about two years before going stagnant.  The golden era of rock music is long gone and will never stage a comeback.  Today’s scene is too fragmented.  Audiophilism has given way to iPod miniaturization, live bands have given way to DJ’s.  At bottom, there’s not enough money in the industry anymore to cull talent and foster rock music communities.

I admire all the Beatles, with a special appreciation for Paul McCartney.  Half of the energy that you hear in early Beatles songs comes from his voice.  He drove the band in their late years.  I especially respect the way he has kept an active career all these years.   You remember his Christmas song and his collaborations with Michael Jackson and Stevie Wonder in the ’80s.  His song “Freedom” was an immediate response to the attacks of 9/11/01.  I saw him live in 2006, when he was touring for his great “Chaos and Creation in the Backyard” album.  The crowd was riveted by “Jenny Wren” just as much as “Yesterday.”  He likes to stay up-to-the-minute on hot new bands.  He has released some orchestral albums that are really good.  He even did some anonymous albums under the band name “Fireman,” which I enjoy as much as any electronica.

Ringo Starr has distanced himself from the Beatles legacy in recent years, so I was glad to see him join Paul at this event.  It seems that he was very excited by it.  Wish I could have been there!  I’m sure tickets were hard to come by.  

If you know where to look, the internet has some very interesting bookshelves, like the basement of a dank library.  I don’t even remember what I was researching recently, when I found myself browsing through the 1921 textbook, “Readings in Evolution, Genetics, and Eugenics” by Horatio Hackett Newman (I swear I’m not making up these names).  On p. 87 (p. 113 of the copy) is this sketch of “The Java ape-man, Pithecanthropus erectus.”  I knew that Java Man had originally been called Pithecanthropus erectus and later reclassified as Homo erectus, though I had never quite understood why.

Now, I’m no paleontologist, but I have been researching Homo erectus quite a lot lately, and I could spot in a moment that this skull didn’t look right.  And what was that dashed line?  Two major facial features didn’t make any sense.  Look at those canines!  (C, below)  Those are “honing” canines.  Chimps, gorillas, and other apes have them, but our hominin ancestors lost them at least 6 million years ago.  What were they doing here on a Homo erectus less than a million years old?  Second, where is his nose?!  Homo erectus had a projecting nasal bone like we do.  This representation shows a concave nose like an African ape (N).  Even for an armchair paleoanthropologist like me, these features stood out as oddly as if someone had drawn a tail on a modern human.     

It occurred to me that the face must have been a guess.  The dashed line was probably a fracture (F below).  If Eugene Dubois, the scientist who discovered Java Man, had only the skullcap to work with, then he would be impressed by the oblong skull (O) and the heavy browridge (B).  These are definitely ape-like (chimp / gorilla) features.  It would only be logical for Dubois to assume — falsely, as it turns out — that the rest of the face was ape-like too.

Not much later, by chance, I happened upon a photograph of the Java Man skull.  Here it is.  The break is shaped a little differently, but indeed, it’s only the skullcap!

Dubois was especially perplexed to find this skullcap with an upright thigh bone.  That’s why he named it Pithecanthropus erectus, “erect ape-man”.  He was envisioning creatures like you’d see on “Planet of the Apes”.  Later discoveries revealed the mistakes, and this species was reassigned to Homo, the human genus.  The resulting term Homo erectus, “erect human”, is redundant and does not describe anything special.  Like non-honing canines, we now know that erect bipedality goes back to the very first hominins.

I am interested in the history of ideas as well as the history of reality.  That’s why I found it such a thrill to discover this rare textbook illustration reminding us of yester-century’s forgotten assumptions.

For further reading, I discuss hominin evolution in How Life Got This Way Chapter 7. Chapter 6 covers early humans, including Homo erectus.