Category Science & Technology

WHAT IS A HYPOTHESIS?

Anyone can make a guess, but scientists set about finding out if their ideas are true in an organized way. A hypothesis is a theory — an idea — about why something happens or what makes something work. A scientist will then try to think of a way of testing whether this idea is correct. Often this will mean designing a special experiment.

A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous observations that cannot satisfactorily be explained with the available scientific theories. Even though the words “hypothesis” and “theory” are often used synonymously, a scientific hypothesis is not the same as a scientific theory. A working hypothesis is a provisionally accepted hypothesis proposed for further research, in a process beginning with an educated guess or thought.

A different meaning of the term hypothesis is used in formal logic, to denote the antecedent of a proposition; thus in the proposition “If P, then Q“, P denotes the hypothesis (or antecedent); Q can be called a consequent. P is the assumption in a (possibly counterfactual) What If question.

The adjective hypothetical, meaning “having the nature of a hypothesis”, or “being assumed to exist as an immediate consequence of a hypothesis”, can refer to any of these meanings of the term “hypothesis”.

HOW HAVE COMPUTERS HELPED SCIENTISTS?

Scientific study relies on collecting and interpreting information (data). Sometimes thousands of different observations or measurements are made. Computers can help to collect and organize the data. For example, an astronomer might want to study the movement of a planet. A computer, attached to a radio telescope, can measure the position of the planet every five minutes for weeks — a task that would be very tedious for a scientist. Having collected the data, the computer can also process it and use it to predict future patterns of movement. Likewise, computers can perform very complex calculations at incredible speed, working out in less than a second something that a century ago might have taken a lifetime to calculate. Other computer programs can draw three-dimensional plans of objects as tiny as an atom or as large as a cathedral. These models can be turned on screen so that all sides can be viewed. Finally, scientists can search for information on the Internet, instead of visiting libraries that may be in other countries.

Science has changed the world. The modern world – full of cars, computers, washing machines, and lawnmowers -simply wouldn’t exist without the scientific knowledge that we’ve gained over the last 200 years. Science has cured diseases, decreased poverty, and allowed us to communicate easily with hundreds of different cultures. The technology that we develop not only helps us in our everyday lives, it also helps scientists increase human knowledge even further.

Science is the pursuit of knowledge about the natural world through systematic observation and experiments. Science is really about the process, not the knowledge itself. It’s a process that allows inconsistent humans to learn in consistent, objective ways. Technology is the application of scientifically gained knowledge for practical purpose, whether in our homes, businesses, or in industry. Today we’re going to discuss how that technological know-how gained through science allows us to expand our scientific knowledge even further.

It’s hard to imagine science without technology. Science is all about collecting data, or in other words, doing experiments. To do an experiment, you need equipment, and even the most basic equipment is technology. Everything from the wheel to a Bunsen burner to a mirror is technology. So all experiments use technology.

But, as technology advances, we are able to do experiments that would have been impossible in the past. We can use spectroscopes (for spectrometers) to shine light through material and see what elements it’s made of. We can use gigantic telescopes to see into the far reaches of our universe. We can use MRI scanners to study the inside of the human body and even the brain itself.

We can use a microscope to see the very tiny. And, we can use electronic devices to take measurements that are far more precise than anything that came before us. Technology is at the heart of all modern science experiments.

HOW ARE EXPERIMENTS DESIGNED?

In the world around us, nothing happens in isolation. One event affects another. The activity of one living thing changes the lives of other organisms. As the natural world is very complicated, it can be difficult to see clearly how and why things are happening. One of the most important factors in designing an experiment is to try to isolate the particular event or substance being studied, so that the results of the experiment are not influenced by other things. For example, to see if a plant needs sunlight to live, you can put it in the dark and watch what happens. But it is important to make sure that the plant still has the same soil, amount of water and temperature as before, so that you can be sure that any changes in the plant are a result of the lack of sunlight.

Many experiments use something called a control. For example, to test a new drug, a hundred people may be given it and their health monitored very carefully. A hundred similar people may be given no drug or a harmless substance and their health monitored just as accurately. They are the control. It is the difference in results between the two groups of people that is important. The control group is designed to show what would have happened to the first group if it had received no drugs. Only then can scientists tell if the drug has had an effect.

An experiment is a type of research method in which you manipulate one or more independent variables and measure their effect on one or more dependent variables. Experimental design means creating a set of procedures to test a hypothesis.

A good experimental design requires a strong understanding of the system you are studying. By first considering the variables and how they are related, you can make predictions that are specific and testable.

How widely and finely you vary your independent variable will determine the level of detail and the external validity of your results. Your decisions about randomization, experimental controls, and independent vs repeated-measures designs will determine the internal validity of your experiment.

Why kilogram has been redefined?

On May 20, 2019, the World Metrology Day, the measurement of a kilogramme was redefined. Earlier, the kilogramme was measured according to the weight of was measured according to the weight of a block of platinum-iridium alloy housed at the International Bureau of Weights and Measures in France. But post May 20, the weight of the kilogramme would be defined by the Planck Constant – a constant of nature that relates to how matter releases energy.

The main problem with using Big K as a universal standard for mass is that Big K, being a manmade object, is imperfect and subject to change over time. Indeed, it is estimated that Big K has lost about 50 micrograms since the time it was created.  Since 1 kilogram is defined as exactly the value of the mass of Big K, if Big K’s mass changes then the value of the kilogram must also change. Obviously, having a standard for mass that changes its mass is not a good idea for science. The ideal set of units should be static and unchanging.

Hence the reason for redefinition. The new definition of the kilogram ties the value of the kilogram to a fundamental constant of nature that will never change. Even billions of years from now when Big K has disintegrated into dust, this new constant the defines the value of the kilogram will be exactly the same—because the value of the unit is tied to a fundamental aspect of reality.

 

Picture Credit : Google

What problems did Google quantum computer solve?

In October 2019, Google claimed quantum supremacy (a point where quantum computers can perform any task that can’t be performed by classical computers) when its quantum computer ‘Sycamore’ performed a complex calculation in 200 seconds. The company claimed that it would take nearly 10,000 years for the world’s fastest supercomputer to perform the same calculation.

Computer scientists have seen quantum supremacy — the moment when a quantum computer could perform an action a conventional computer couldn’t — as an elusive, important milestone for their field. There are many research groups working on quantum computers and applications, but it appears Google has beaten its rivals to this milestone.

According to John Preskill, the Caltech particle physicist who coined the term “quantum supremacy,” Google’s quantum computer “is something new in the exploration of nature. These systems are doing things that are unprecedented.”

It sounds all very gee-whiz. And some scientists think these computers will one day lead to discoveries of new drugs and possibly whole new fields of chemistry. Others fear they’ll be used one day to crack the toughest security protocols.

 

Picture Credit : Google

When did the first hybrid ancient human found?

In 2018, scientists studying ancient DNA revealed to have found the first hybrid ancient human. The DNA, sourced from a 90,000-years-old bone, belonged to a teenage girl whose father was a Denisovan and mother was a Neanderthal.

This is the first time scientists have identified an ancient individual whose parents belonged to distinct human groups. The findings were published on 22 August in Nature.

“To find a first-generation person of mixed ancestry from these groups is absolutely extraordinary,” says population geneticist Pontus Skoglund at the Francis Crick Institute in London. “It’s really great science coupled with a little bit of luck.”

The team, led by palaeogeneticists Viviane Slon and Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, conducted the genome analysis on a single bone fragment recovered from Denisova Cave in the Altai Mountains of Russia. This cave lends its name to the ‘Denisovans’, a group of extinct humans first identified on the basis of DNA sequences from the tip of a finger bone discovered2 there in 2008. The Altai region, and the cave specifically, were also home to Neanderthals.

 

Picture Credit : Google