String theory

मैं समझता हूँ कि विज्ञान की सामान्य रुचि रखने वाले हर मनुष्य ने यह सुना होगा कि हमारे ब्रह्मांड का मूलभूत ढांचा यानी "स्पेसटाइम" स्ट्रिंग्स से बना है। सूक्ष्म जगत में मौजूद ये तंतुनुमा स्ट्रिंग्स वाइब्रेशन (कंपन) करते हैं तो इनसे स्पेसटाइम में तरंगे पैदा होती हैं, जिन तरंगों को हम "पदार्थ" के रूप में ग्रहण करते हैं। आइए, आज आपको इन स्ट्रिंग्स के बारे में कुछ मजेदार बातें बताता हूँ। इन स्ट्रिंग्स का आकार बेहद छोटा यानी 10^-35 मीटर है, अर्थात दशमलव के बाद 35 शून्य मीटर । बेहद छोटा होने के बावजूद इन स्ट्रिंग्स में बेहद प्रचंड तनाव है। अर्थात अगर आपको इन स्ट्रिंग्स को छू कर किसी गिटार के तार की तरह कंपन कराना है, इसके लिए आपको बहुत ज्यादा ताकत लगानी पड़ेगी। कितनी ताकत ? वैल, इन स्ट्रिंग्स में निहित मूलभूत तनाव 10^39 टन है। यानी इसे वाइब्रेट कराने के लिए उतनी ही ताकत चाहिए, जितनी ताकत आपको इस पूरी मिल्की-वे गैलेक्सी के बराबर भारी चीज को अपनी जगह से हिलाने में लगेगी। इतनी ताकत सिर्फ एक स्ट्रिंग को हिलाने के लिए। है न कमाल बात ? इन स्ट्रिंग्स द्वारा पैदा किए गए सबसे छोटे कंपन (तरंग) की ऊर्जा भी प्रोटॉन से 10 लाख खरब (10^19) गुना ज्यादा होती है। सरल शब्दों में इन स्ट्रिंग्स द्वारा निर्मित सबसे छोटे कण की ऊर्जा भी प्रोटॉन से खरबों गुना ज्यादा होती है। अगर ऐसा है, तो कम द्रव्यमान वाले पार्टिकल्स इस दुनिया में मौजूद हैं ही क्यों? वो इसलिए, क्योंकि दृश्य ब्रह्मांड में लगभग 1080 (10 के आगे 80 शून्य) स्ट्रिंग्स हैं और कोई भी स्ट्रिंग डायरेक्टली किसी कण की रचना नहीं करती। वास्तव मे ं इन स्ट्रिंग्स से पैदा हुई शक्तिशाली तरंगे पहले एक-दूसरे से टकराती हैं, एक-दूसरे को कैंसिल आउट अथवा मैग्नीफाई करती हैं। नए-नए वेव पैटर्न्स पैदा होते हैं। इस तरह खरबों खरब वेव कैंसलेशन के बाद अंततः जो वेव्स शेष रह जाती हैं, उन्हें हम पदार्थ कणो ंके रूप में ग्रहण करते हैं। अब अगर आपको स्टिंग के थरथराने से लेकर पदार्थ कणों तक की उत्पत्ति तक का गणित तलाशना हो तो यह कुछ ऐसा मानो  संसार में खरबों लोग जेब में खरबों रुपये लेकर शॉपिंग को निकले और आपको बिना उनसे कोई भी जानकारी लिए बस अनुमान के आधार पर यह ज्ञात करना है कि उन्होंने पूरे दिन क्या-क्या खरीदा, कितने पैसे एक-दूसरे को दिए, कितने पैसे वेस्ट हो गए - जिसके बाद अंततः संसार में 189 रुपये बचे। मुश्किल है न? बस इसी से आप समझ जाइए कि स्ट्रिंग थ्योरी का गणित कितना मुश्किल है और स्ट्रिंग थ्योरी को सुलझाने में वैज्ञानिकों के पसीने क्यों छूटे हुए है। खैर, इतिहास गवाह है कि मनुष्य की मेधा के सामने समर्पण कर देना ही हर रहस्य की अंतिम नियति रही है। स्ट्रिंग्स के पेंचीदा गणित रहस्य एक दिन अवश्य धराशायी होगा। 

C V Raman

 Chandrasekhara Venkata Raman was born in 1888 in a village in southern India. As a child, Raman was precocious, curious and highly intelligent. His father was a college lecturer in mathematics, physics and physical geography, so the young Raman had immediate access to a wealth of scientific volumes. By the age of 13, he had read Helmholtz’s Popular Lectures on Scientific Subjects.

Raman was deeply interested in music and acoustics. While in college, he read the scientific papers of Lord Rayleigh and his treatise on sound as well as the English translation of Helmholtz’s The Sensations of Tone. This initiated Raman’s later interest in the physics of drums and stringed instruments such as the violin. He used fine-chalk powder and photography to investigate the vibrational nodes of drums; the white chalk remained only at the nodes of the vibrating membrane.

In a culturally anomolous and brazen act, when Raman was 18, he arranged his own marriage to Lokasundari (later called Lady Raman), a 13-year-old woman from Madras. The two then moved to Calcutta, where Raman accepted a position in the Indian Finance Department. During the next ten years—from 1907 to 1917—he struggled to balance his well-paying government job with his drive to be a scientist.

When he wasn’t at the Finance Department, he was conducting experiments at the Indian Association for the Cultivation of Sciences (IACS) in Calcutta. The IACS had been formed along the pattern of the Royal Institution in London. Its journal Proceedings was renamed the Indian Journal of Physics in 1926. Raman’s early works become known to an international audience when he published his research in the journals Nature, Philosophical Magazine and the Physical Review.

By 1917, Raman had had enough of his double life. He quit his government position and devoted himself fully to science. He accepted a full-time professorship—the endowed Pailt Chair of Physics—at Calcutta University, where he remained for 15 years.

One of the requirements of that position was to obtain training abroad in order to achieve parity with foreign professionals. Confident in his genius, Raman claimed that he did not need any foreign training; on the contrary, he was prepared to train those from other countries. Moreover, he argued, he had already earned a prestigious international reputation in physics due to his publications. Since Raman refused to budge, the University had no choice but to waive this requirement in order to secure the rising star. In 1924, Raman was elected a Fellow of the Royal Society. It is as if he knew he was destined for greatness. Indeed, in 1925, when Raman was attempting to obtain funds to purchase a spectroscope, he told his benefactor: “If I have it, I think I can get a Nobel Prize for India.”

In 1933, Raman became director and professor at the Indian Institute of Science (IIS) at Bangalore. The next year, he established the Indian Academy of Sciences. Over the following decade, he published more than 30 papers in the Proceedings of the Indian Association for the Cultivation of Science, Nature, Philosophical Magazine and Physical Review. In 1937, he quit his position following disputes with some staff and members of the Council of the IIS.

At the age of 60, Raman then formed the Raman Research Institute (supported with his own funds and donations that he raised). He also remained a professor, as well as the President of the Indian Academy of Sciences in Bangalore, until his death in 1970.

The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It

One of the more unsettling discoveries in the past half a century is that the universe is not locally real. In this context, “real” means that objects have definite properties independent of observation—an apple can be red even when no one is looking. “Local” means that objects can be influenced only by their surroundings and that any influence cannot travel faster than light. Investigations at the frontiers of quantum physics have found that these things cannot both be true. Instead the evidence shows that objects are not influenced solely by their surroundings, and they may also lack definite properties prior to measurement.

This is, of course, deeply contrary to our everyday experiences. As Albert Einstein once bemoaned to a friend, “Do you really believe the moon is not there when you are not looking at it?” To adapt a phrase from author Douglas Adams, the demise of local realism has made a lot of people very angry and has been widely regarded as a bad move.

Blame for this achievement has been laid squarely on the shoulders of three physicists: John Clauser, Alain Aspect and Anton Zeilinger. They equally split the 2022 Nobel Prize in Physics “for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science.”