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08/05/2016
Things Large and Small
CHAPTER 71 Nothing
I'm posting this column much later than usual thanks to greater time spent on various care-giving duties after my wife fell in the bedroom last week and has had a lot of severe back pain. Thankfully, her doctor just examined her and concluded that she had not broken any bones and that her pain was of a muscular variety that would work itself out. A few weeks ago I also fell. My fall was due to my tripping on a step at the brick platform leading to the 8th tee at our municipal par-3 golf course. And I was having one of my better rounds in our Old Guard golf group. My only injuries were bruises on my forehead, nose and knees, together with a significant bloody elbow cut that spattered blood all over my white slacks. My only other significant fall was years ago, also on a golf course. Then, I broke my leg and still have a metal plate near the ankle of my left foot. This was on the same hole I previously had carded my only hole-in-one. Longtime readers will know I take any occasion to mention that hole-in-one.
While tending to my wife a couple days ago I saw Kathy Lee Gifford and Regis Philbin on the Today show on NBC. Regis was filling in for the normal co-host, Hoda Kotb, who is in Rio covering the Olympics. Kathy Lee was talking about how, years ago when she and Regis were popular co-hosts on a morning show on TV, someone said their show was about nothing. She noted that later the Seinfeld series on TV was also deemed a show about nothing. Well, I was reading my August issue of Scientific American and the article featured on the cover is an article about, you guessed it, nothing. The article, titled "The Emptiest Place in Space" is by Istvahn Szapudi, an astronomer at the University of Hawaii's Institute of Astronomy.
Szapudi specializes in studies of the large scale structure of the universe. Regular readers of this column will know I'm a sucker for anything dealing with the universe. Szapudi begins his article by pointing out that if you have an old TV and tune it between channels, the specs you see dancing on the screen are caused by the oldest light in the universe, the cosmic microwave background (CMB) radiation from the big bang 13.8 billion years ago. I've certainly written enough about the Big Bang over the years and feel a personal connection to the CMB. (Szapudi does not capitalize "big bang", but I feel that it's sufficiently monumental that I always capitalize it.) As I'm sure I've mentioned before, I never met Arno Penzias, who with Robert Wilson, got the Nobel Prize for discovering the CMB, confirming the existence of the Big Bang. The closest I ever got to Penzias was sitting at the next table at lunch in the Bell Labs dining room but I do have a personal letter from him urging me to accept an invitation to write something concerning a paper I published. Hence my feeble personal connection to the Big Bang.
OK, that's a stretch. Back to nothing. Over the years exhaustive studies have been done on mapping the CMB, whose photons have a temperature on average of a very low 2.7 degrees Kelvin, close to absolute zero. Whether you know it or not, I'm sure you have seen in the media maps of the CMB with colors representing minute variations in the temperatures of the CMB from various parts of the universe. The map is sometimes called the birthday picture of our universe. What intrigued Szapudi and his colleagues is the presence of a "cold spot" in the map of CMB. In this cold spot, the width of which is an area of the sky about 20 times the width a full moon, the temperatures of the photons are significantly cooler than the other photons in the map.
Szapudi and his colleagues speculated that the cold spot corresponded to a portion of the universe where there was nothing, at least relatively speaking. Thus began a monumental mapping of the universe that we can see. The effort involved a huge amount of mapping the galaxies in the region of the cold spot. As I understand it, the effort involved measuring the red shift in the light from the galaxies. The more shifted the light from the galaxy the farther away it is. My impression is that they took the data and essentially came up with sheets of cross sections, corresponding to the distribution of galaxies at different depths in the universe in the area of the cold spot. Sure enough, when the painstaking effort was finished there was a region where, compared to the rest of the surrounding universe, there is a void in which there are relatively no galaxies, that is a huge void with nothing, relatively speaking. And the region corresponds to the cold spot.
Why is the void colder than its surroundings? It's the integrated Sachs-Wolfe effect. I won't pretend to understand this. It has something to do with photons entering the void and losing energy that the photons don't gain back when they leave the void, which apparently is what would happen if the universe were not expanding. Anyway, the astronomers seem to know what happens. Not that there isn't controversy about the correlation of a void with the cold spot. It seems the size of the void isn't large enough to explain the temperature of the cold spot and some are questioning the explanation of the coldness as being due to the "nothingness" of the void. Critics propose that it's just a coincidence that the cold spot and a void lie in the same region of the universe. The size of the void is huge, some 1.8 billion light-years across. However, the size and shape is not known and a major effort is underway to determine the three-dimensional shape of the void. The possibility exists that the results could lead to an understanding of the mysterious dark energy that is driving the expansion of our universe.
Well, I was actually initially thinking of writing about something that is making headlines these days but is size-wise also like nothing, certainly if compared to the size of the void discussed above. I'm talking about the Zika virus and the mosquito carrying Zika. Of all the articles and news reports I've seen or read on the subject, I found two articles in the August issue of National Geographic to be most informative and interesting. One article titled "DNA Revolution" is by Michael Specter and the other, "Science vs. Mosquitoes" is by Cynthia Gorney, who writes "To this day, insects smaller than a child's thumbnail remain the most dangerous nonhuman animals on this planet." While the Zika virus and the mosquitoes that carry it get the most media coverage these days, mosquitoes carrying malaria kill over 400,000 people a year. (Scouring the Internet, I've seen estimates as high as 600,000 killed a year by malaria.)
When the Ae. aegypti mosquito bites into you and sucks your blood, she uses a multipronged proboscis to slip under your skin, inject her saliva with an anticoagulant and may double her weight with your blood. And you may not know she bit you until she has flown off to rest with her heavy load. She only lives for about a month but only needs one mating with her plant-eating male cohort to lay hundreds of eggs! No wonder efforts to exterminate the deadly pest typically fail.
So what's the future? Hopefully, the answer may lie in the use of one of the most important discoveries of my lifetime, CRISPR-Cas9, just plain CRISPR for short. I would call the discovery and decoding of DNA the most important biological achievement of the 20th century. CRISPR is, in my opinion, the most important discovery of this 21st century. CRISPR allows researchers one to select regions of DNA, cut them out and replace or rearrange them. I won't try to go into detail on how CRISPR works but the technique is so versatile and relatively easy to use that when I get my copies of Science in the mail there are sometimes advertisements for CRISPR kits of some sort. Bad genes can be targeted and removed, offering the potential to cure or prevent diseases. In his article Specter writes that "No scientific discovery of the past century holds more promise - or raises more troubling ethical questions."
Obvious uses of CRISPR would be to remove disease-causing genes from embryos, that is, tinker with the DNA of an embryo in the womb to prevent some terrible disease. A laudable goal but whatever change is made it could get passed down to succeeding generations. Carried to an obviously unjustified extreme, would you want to modify a gene to assure a blue-eyed blond baby? Obviously, I think ethicists would deem that unacceptable. What about pigs? Apparently, there is now work that shows the possibility that by tinkering with pig genes pig hearts may be rid of the characteristics or diseases that make them unsuitable for transplanting into humans.
Getting back to mosquitoes, there is already work showing that by tinkering with mosquito genes mosquitoes can be bred that when mated only produce male offspring. The proposal here is to breed and release large numbers of these mosquitoes in the hope that we could vastly reduce malaria or Zika carrying mosquitoes, possibly eliminating mosquitoes all together. If we did eliminate all mosquitoes what would be the effect on the environment? The ethical and scientific questions raised by the advent of CRISPR are enormous and we'd better start serious scientific and ethical programs/projects to address them.
Would you believe that I actually had started a draft of this column last week with a fairly long critique of Donald Trump? I'm not going to include that material but will conclude by returning to the subject of nothing. Is there nothing that The Donald will say that will not help to insure that Hillary becomes our next president?
Next column, hopefully, on or about September 1.
Allen F. Bortrum
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