SCI-ART LAB

Science, Art, Litt, Science based Art & Science Communication

Q: Does gravity effect the food movement in the digestive system in any way? 

Krishna: Though experts warn against eating while lying down, this suggestion isn't related to gravity in any way. That’s because digestion is aided not by physics, but by peristalsis—the contracting of muscles along the digestive tract to transport food through the body. It explains why astronauts are able to digest their space spaghetti in zero-gravity conditions.

Q: Can we eat our food lying down?

Krishna: Lying on one’s left side can reduce pressure on the lower stomach, allowing one to eat more comfortably. It may also allow carbohydrates to be absorbed more slowly, and therefore prevent spikes in insulin levels, but that’s pretty much where the benefits end. It could also lead to an increased risk of gastroesophageal reflux disease (GERD), and the American College of Gastroenterology recommends that people avoid lying down for two hours after eating.

Also, the food might enter your wind pipe accidentally if you eat lying down and can lead to choking. Your Posture will have effect on digestion. The posture you adopt while eating can influence your ability to digest food. That's because food empties from the stomach more slowly when a person is sitting in a slumping position or lying down, compared to when they are standing or sitting straight.

Q: How can any individual claim the apex of knowledge?

Because this universe is based on scientific principles and run by science in reality.

To reach “Apex of knowledge”, we, as human beings have several limitations. What you think is real knowledge might be just your interpretation and need not be a fact.

Therefore, to overcome all human weaknesses in interpreting things science has set some rules. Scientific method … validification, falsification, improvement.

Our Universe is based on and follows certain scientific principles ... that is established science. If it is not, our universe would have collapsed by now. As it is working wonderfully, the universe has clearly demarcated what is science and what is not. If your study agrees with the universal science, it is undoubtedly 'scientific'. Nobody can challenge and provide evidence contrary to that. Universal science is settled.

While Science is what our universe works with and a settled one at that, science is also the process with which we try to understand things. It’s about explaining the world we see, developing models that fit the data. But fitting models to data is a complex and multifaceted process. In this process the universe itself is our guide. Human mind might not be able to comprehend fully and correctly sometimes because of its limitations, but there are processes called falsifications and corrections to set things right. It is because of the human mind limitations, we most often have only the best knowledge under the present circumstances. If we get things right, and if our data fits with the universal versions there won't be any falsification and it is the ultimate knowledge.

If what we observe concurs with the universal principles of science, that itself is evidence that we got it right. If we can make things work using our new found knowledge ( inventions based on discoveries), that itself is proof we got things right.

What demarcates science from nonsense

Science and Spirituality

Q: How have you overcome silly beliefs and practices? Can you guide me too?

First my training in scientific research made me question everything and analyse in detail and think critically.

My understanding of the world around me in a scientific and realistic way made me overcome all fear. I no longer fear anything. That understanding and conquering of fear made me discard all nonsense.

My grandfather was a social reformer. My upbringing too helped me to some extent.

But then, I am now completely different from everybody around. People don’t understand and appreciate what I do, i.e., swimming against the tide. They try to bring me back to their ways of doing things.

But I stopped caring about what others think about me. I stopped caring about others judgments, opinions, and silly talk about me. Nothing bothers me anymore.

My only guide is my science and critical thinking it gave me. Rest all belongs to trash can.

A mind broadened by genuine knowledge can never go back to its original size.

I am completely in a peaceful state of mind now.

Yes, I can guide you and all the others who want to follow a scientific way of life. 

Just read what I write and post here and then ask me questions if you find any difficulty. 

Q: I have migraine and diabetes problems and am on insulin. I am facing severe problems because of them. 

My in-laws and husband are highly orthodox. They won't eat anything unless they perform pujas which might take three to four hours to complete in the morning.  They won't allow me too to eat anything until they complete all their rituals. They say God will protect me if I follow what they tell me to do. But I have to work at home and send my children to school. If I don't eat in the morning, I get severe headaches, my blood sugar levels go down making me feel giddy.  What is the solution? No amount of pleading could change the people in my home. Shall I eat without their knowledge? Is that right thing to do?

Krishna: I have seen some people like your husband who don't have any knowledge about human body. And those who don't try to understand others' plight no matter how much you try. 

What is right and what is wrong in such circumstances? As a biologist, I think eating something is right. But do it smartly.

Take the things you want to eat and keep them before the idols you worship, offer them to your 'God' and then eat them and tell your folks that you are eating only Prasad.   And God wanted you to eat them to recover from your health conditions.

That will be alright in their view. 

Q: Can God worship cure diseases?

Krishna: No, it doesn’t! You yourself can try and see the results. If only praying to God can cure diseases, nobody would suffer. If praying can save you from death, nobody would die.

On the other hand, science can help you in curing at least some diseases. You might ask, ‘why not all?’. The limitations come from our understanding of the diseases.

This universe is controlled by science and run by it. If you can understand this, you can solve the problems using the knowledge.

Science's rules are unyielding, they will not be bent in any way fo...

ScienceDirect ( Clinical investigation had been done on this and a paper too was published: Study of the Therapeutic Effects of Intercessory Prayer (STEP) in cardiac bypass patients: A multicenter randomized trial of uncertainty and certainty of receiving intercessory prayer 

Results : In the 2 groups uncertain about receiving intercessory prayer, complications occurred in 52% (315/604) of patients who received intercessory prayer versus 51% (304/597) of those who did not (relative risk 1.02, 95% CI 0.92-1.15). Complications occurred in 59% (352/601) of patients certain of receiving intercessory prayer compared with the 52% (315/604) of those uncertain of receiving intercessory prayer (relative risk 1.14, 95% CI 1.02-1.28). Major events and 30-day mortality were similar across the 3 groups.

Conclusions : Intercessory prayer itself had no effect on complication-free recovery from CABG, but certainty of receiving intercessory prayer was associated with a higher incidence of complications.

https://www.sciencedirect.com/science/article/pii/S0002870305006496...

So?!

In 1936, a young girl in New York named Phyllis sent Albert Einstein a letter asking him whether scientists prayed. In the letter, posted by Brain Pickings from a larger volume of Einstein's letters answering children's' questions, he replied that since scientists believe that everything in the world must fall under the laws of nature, they don't believe that a wish can be granted by a supernatural force.

Scientists think that every occurrence, including the affairs of human beings, is due to the laws of nature. Therefore a scientist cannot be inclined to believe that the course of events can be influenced by prayer, that is, by a supernaturally manifested wish.

Q: Are all mutated pathogens resistant to antibiotics?

Q: Why is religion widely accepted instead of science? Do you believe in religion?

Do you believe in religion or science?

Do you believe in it? No, I don’t believe in religions.

Why is religion widely accepted? 

Because of .... 

Lack of critical thinking skills.

Emotional dependence on ‘your groups’ and ‘your God’.

Fear of the unknown.

Filling the gaps created by your inadequacy of understanding the things around you with strange unverified stories and explanations.

Falling prey to vested interests’ designs because of lack of mental strength.

Difficulty in understanding Science, despite our efforts to make it simple.

I do trust, not believe, in science. Because it is the best that can get you to the facts of this universe and help us overcome our problems when we use the knowledge correctly.

Q: What is the science behind that near -perfect rectangular iceberg?

Pic source: Google images

Krishna: Ice has a crystal structure that means it prefers to break along straight lines. In the northern hemisphere, ice sheets sit on bedrock, and the friction between the ice and the ground means icebergs form in the irregular shapes that most of us picture when thinking of an iceberg.

In contrast, the edges of the near-perfect rectangular Antarctic ice sheet are mainly made of floating ice shelves. These ice slabs are free to break along their natural crystal structure, resulting in icebergs that often have straight edges and smooth tops. We often see icebergs with geometric shapes, although such a perfect rectangle is admittedly unusual. The walls of this new iceberg are sharp and almost perfectly vertical, suggesting they formed recently and small. As time goes on, waves will start to erode these edges, creating large arches and caving in its walls.

Q: When two experts or scientists answered or explained things vastly different from each other, who should we believe in?

Krishna: Very good Q. I myself faced similar situations several times. But I am trained in scientific methods, critical thinking and have some basic knowledge in almost all the fields of science. Therefore, I can identify the correct answer or explanation by going into the details provided. 

I agree, some scientists bring their biases, pseudo-knowledge, misconceptions, strange interpretations to argue their cases.   As a person of science, I can identify this deceit.

I usually look for the credentials of the person explaining the things. If s/he is a subject expert, you can trust the person, but also should give your brain some work before doing that. If a scientist who belongs to a different field  explains things, you should use your critical thinking abilities to find out whether the explanation is correct or not.

Let me give an example. Two scientists were asked a Q recently: Do clouds actually help fighter planes stay off radar? The two answered the Q quite differently. 

The first one, a scientist in food technology ( who has no correct knowledge about radars), said this: 

Two technical terms, Stealth technology and Stealth aircraft.

I bet some of our ministers have never heard or read of Stealth Technology or Stealth Aircraft. Even if somebody tells them about these, I am sure they won't be able to pronounce or spell them properly because their Streanh lies somewhere else.

I came to know about Stealth Technology and Stealth Aircraft for the first time when the US Navy Seals boarded on US fighter helicopters- Black Hawks, flew from Afghanistan and stealthily landed in Abbottabad, shot Osama Bin Laden, picked up his dead corpse and buried in Arabian sea on the way back home.[2]

The Black Hawks used previously unseen "stealth" versions of the helicopter that fly more quietly and are harder to detect on radar than conventional models; due to the weight of the extra stealth equipment on the Black Hawks, cargo was "calculated to the ounce, with the weather factored in.[3]

The United States of America, especially Lockheed Martin has spend billions of dollars and is still investing many more in the R&D of Stealth Aircrafts[4]so that their aircrafts become absolutely invisible to any radar.

I really pity the USA that they don’t have a Supreme Leader like our PM, who we have here in India and whose raw wisdom about clouds in sky can make our Indian fighter jets undetectable to Pakistan’s Radars. I guess, now onwards, all our fighter pilots would wait for the thick blanket of clouds to appear in the sky so that they can air-attack Pakistan. This way, the monsoon season would also become the season of air strikes all over the world. I believe, North Korea would every year just wait for the monsoon so that its fighter jets become undetectable to military radars of South Korea.

2] Death of Osama bin Laden - Wikipedia

[3] Attack on Bin Laden Used Special Radar-Evading Helicopter

[4] F-117 Nighthawk

Another scientist, who actually works with radars gave this answer: 

In the link budget analysis for satellite communication, rainfall/cloud cover generally accounts for 2-3 dB loss in L-band and S-band.

In the primary radars, the signal has to travel back from the aircraft. Thus, rain will account for >6 dB attenuation at least. The loss's exact value depends on frequency and the amount of rainfall/thickness of cloud cover but it nevertheless exists.

Radars of both F-16 (AN/APG-68 - Wikipedia) and JF-17 (KLJ-7 - Wikipedia) operate in X-band (8–12 GHz). I'm not aware of the SAMs used by PAF, but their radars would also operate in X-band because of the resolution in detection that is needed for anti-aircraft operations.

Please go through the webpage: Radar Basics . It shows a loss of 10 dB/Km in X-band for rainfall which means power is reduced to 1/10th of its original value.

Continuous Wave radar range decreases by 4th root of power - Radar Range Equation . Thus, a 10 dB/Km loss in power reduces the range to 57% of its original value.

For thicker rainfall/cloud cover, the loss would be even more, thereby reducing the range even further.

During my internship in L-band radar section at ATC, IGI airport, I was told that rainfall/cloud cover results in 2-3 dB reduction in power. Please note that L-band radars operate in 1–2 GHz range in which loss is lower as compared to X-band.

So, from at least 3 sources, I know that rainfall/cloud cover results in reduction in radar's range.

This is known to everyone in civil and military aviation. The same might have been told to the PM by the air force officers before the air strikes. I'm amazed at his sharpness of mind that he could understand details of radar operation despite his age and could also convey to a large audience or maybe, whatever he said was a fluke. But it is technically correct. I request people to not mix engineering with politics.

You have touched 2 different points - Communication between ATC and planes and Detection/Surveillance. They both are done in different frequency ranges and are completely unrelated to each other.

  1. In civil aviation, communication is done in HF/VHF frequency range. For long distances over seas and oceans, Sky-wave propagation is used in HF range (3–30 MHz). Over land, VHF frequency range is used. In VHF range, signal passes through the ionosphere and doesn’t reflect from it. So it is essentially LOS communication. At such low frequencies (lower than microwave), attenuation due to water vapors in cloud/droplets in rainfall is very very low - orders of magnitude lower than that in microwave region. So, it is not affected much by rain.
  2. For surveillance, Radars operating in microwave region are used. These radars work in L-band (1–2 GHz), S-band (2–4 GHz), C-Band (4–8 GHz) and X-band (8–12 GHz). L-band radars have range in excess of 400 Km but their resolution is lowest. So they are used for long range surveillance. On the other hand, X-band radars have range of ~20 Km but there resolution is highest. So they are used for monitoring airplanes present inside the boundary of the airport.

It is not impossible to understand why lower frequency (i.e. higher wavelength) radars have higher range. It is because they are least dispersed/scattered by the air/dust/water molecules.

In the same way, rainfall/heavy cloud cover provides heavy attenuation to the radars working in X-band, much higher than that in L-band. As a result, THE RANGE IS REDUCED. But when the plane is within the range, it can be perfectly detected by the modern radars.

So, there are 2 different phenomenons at work here -

  1. Reduction in radar’s range due to attenuation of EM waves caused by scattering. I have shown some calculations in my answer. You can refer to it one more time.
  2. Detection of planes using the echos received from the planes that lie in the new reduced range. Radar will also receive false echos from the clouds that lie within its reduced range. It employs advanced DSP algorithms to remove these false echos.

I hope you could understand the difference between communication and surveillance properly. I hope you could also understand why X-band radars receives heavy attenuation from rain/clouds.

Bonus point - Generally, radar antenna array emits linearly polarized EM waves during clear weather. But during rainfall/heavy cloud/fog cover, they are switched to circular polarization.

Since water droplets are approximately circular in shape, their echos can be easily removed at the receiver. Airplanes are not circular at all, hence their echos remain. Therefore, within its range (read reduced range), a modern radar can perfectly see through the clouds/rain. It is also important to know that switching from linear to circular polarization reduces power further by 3dB.

For even detailed information please read introduction of this paper -Electromagnetic wave propagation in rain and polarization effects

To know how the false echos are cancelled please read section 3.7.4.6 of this paper -ScienceDirect\

Another attempt at explaining the difference between reduction in range and detection - partially taken from another reply of mine on a comment.

Range reduction and detection are two different things!! Range reduction is due to attenuation caused by the wireless channel. Nothing can be done about it!! Detection is performed by the receiver. It can only detect what lies in its range!!

STEALTH/GROUND HUGGING TECHNOLOGY IS USED TO EVADE RADARS WHEN THE PLANE IS IN ITS RANGE IN THE FIRST PLACE!! Any X-Band radar will not pick signatures of any plane 1000 KM away from it. It is because it is out of its range. It is not as difficult thing to understand as it has been made out to be by some readers.

What do you think?

I think the second one, a specialist in the field, gave a good answer while the first scientist, who 's no expert just expressed his biased views using some jargon. 

Now did you understand the difference?

So some knowledge in science, Critical Thinking  , credentials of the person who explains things, the evidence provided should help you decide who is giving the right explanation.

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