Observation
From Wikipedia, the free encyclopedia
- For other uses, see Observation (disambiguation).
Observation is an activity of a sapient or sentient living being, which senses and assimiliates the knowledge of a phenomenon in its framework of previous knowledge and ideas.
However, personal observations gathered without the aid of instruments are often unreliable¹ and not always reproducible. Therefore they are not of much use in exact sciences like physics. It is therefore often necessary to use various instruments like: spectrometers, oscilloscopes, cameras, telescopes, interferometers, taperecorders, thermometers etc. and tools like clocks, scale that help in improving the accuracy, quality and utility of the information obtained from an observation. Observation invariably requires logical thinking as logic is necessary for assimiliation of the knowledge that is presented by an observation.
The accuracy and tremendous success of science is primarily attributed to the accuracy and objectivity of observation of the reality that science explores.
It is uncertain that reality can be observed at all.
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[edit] The role of observation in the scientific method
The scientific method includes the following steps:
- 'observe' a phenomenon,
- 'Hypothesize' an explanation for the phenomenon,
- 'predict' a logical consequence of the guess,
- 'Test' the prediction, and
- 'review' for any mistakes.
Observation plays a role in the first and fourth steps in the above list. Reliance is placed upon the five physical senses: visual perception, hearing (sense), taste, feeling, and olfaction, and upon measurement techniques. It is therefore understood that there are always certain limitations in making observations.
[edit] Example - The Big Bang
In cosmology, the original observation was that we seem to live on a flat Earth under hemispherical firmament. The sun seemed to rise and set, travelling on a huge transparent bowl which was set around our world. Various paradigms which explained our world, came and went, but the universe seemed static. Even Einstein believed this.
[edit] Observation: Hubble's redshift
In the 1920s Edwin Hubble of Mount Wilson observatory [1], observed that the galaxies, on the whole, were moving away from each other. Thus we live in an 'expanding universe'. The speed of expansion was apparently constant (Hubble's 'constant'), as evidenced by light from the galaxies, which was doppler-shifted in color toward the red side of the spectrum.
Einstein correspondingly modified his field equation. See Cosmological constant
[edit] Hypothesis about the abundance of the elements
If the universe is expanding, then it must have been much smaller and therefore hotter and denser in the past. George Gamow hypothesized that the abundance of the elements in the Periodic Table of the Elements, might be accounted for by nuclear reactions in a hot dense universe. He was disputed by Fred Hoyle, who invented the term 'Big Bang' to disparage it. Fermi and others noted that this process would have stopped after only the light elements were created, and thus did not account for the abundance of heavier elements.
Gamow's prediction: One consequence of this hypothesis was a 5–10 kelvin black body radiation temperature for the universe, after it cooled during the expansion.
[edit] Observation: the microwave background
In 1965, Arno A. Penzias and Robert W. Wilson announced that microwave radiation was surrounding us in all directions, at a level which was of the order of magnitude predicted by Gamow. Penzias and Wilson got the Nobel Prize for this discovery.
[edit] Big Bang Hypothesis now corroborated
After this piece of evidence, Gamow's hypothesis was now more likely. The age of the universe is currently estimated to be 13.7 billion years after the Big Bang.
[edit] Current observations
More refined measurements, such as those from the COBE satellite, are best fit by radiation from a pure 2.7 kelvin black body.
[edit] Future observations
It is, of course, entirely possible that observations made in the future may enable a different understanding. People of the future, looking back on the Big Bang theory may, perhaps, regard it with as much derision as the people of today regard the apparent geocentric universe of previous observations. All that is possible is to keep looking at the evidence as it comes in.
Reference: J.A. Peacock, A.F. Heavens, A.T. Davies (eds.), 1989. Physics of the Early Universe. Proceedings of the 36th Scottish Universities Summer School in Physics (SUSSP). ISBN 0-905945-19-0.
[edit] The role of observation in philosophy
"Observe always that everything is the result of a change, and get used to thinking that there is nothing Nature loves so well as to change existing forms and to make new ones like them." Meditations. iv. 36. -Marcus Aurelius
Observation in philosophical terms is the process of filtering sensory information through the thought process. Input is received via hearing, sight, smell, taste, or touch and then analyzed through either rational or irrational thought. You see a parent beat their child; you observe that such an action is either good or bad. Deductions about what behaviors are good or bad may be based on preferences about building relationships, or study of the consequences resulting from the observed behavior. With the passage of time, impressions stored in the consciousness about many related observations, together with the resulting relationships and consequences, permit the individual to build a construct about the moral implications of behavior.
The defining characteristic of observation is that it involves drawing conclusions, as well as building personal views about how to handle similar situations in the future, rather than simply registering that something has happened.
Observing is part of the process of developing a morality.
