From: mk_thisisit
Professor Maciej Lewenstein is recognized as one of Poland’s most outstanding physicists [01:07:09]. His research has significantly contributed to the understanding and generation of incredibly short light impulses, which were central to a recent Nobel Prize in Physics [01:10:09].
Attosecond Pulses and High Harmonics
The Nobel Prize acknowledged the creation of “great impulse lasting less than one billionth of a billionth of a second” [01:17:09], which allows scientists to look inside the atom [01:22:09]. These impulses, lasting less than a millionth of a millionth of a millionth of a second [01:45:09], operate on attosecond timescales, which are 1000 times smaller than femtoseconds [04:58:09].
Lewenstein’s work in the 1990s, alongside a Nobel Prize winner, led to a fundamental article in attosecond physics [05:05:09]. This article described the process of generating attosecond pulses, a phenomenon known as “high harmonics generation” [05:35:09]. This involves shining a strong, short laser pulse onto a target (atoms or molecules), which excites them to produce photons with frequencies that are multiples (harmonics) of the original laser frequency [05:55:09].
The process is often explained by the “three-stage model” or “simple man model,” which is classical [08:10:09]. However, Professor Lewenstein’s key contribution was formulating this process using a fully quantum description [09:02:09], known today as the “strong field approximation” [09:09:09]. This paper, primarily his work, is widely known as the “Lewenstein model” [10:50:09] [00:30:09]. It provided simple, quantitatively useful formulas for experimenters to compare with their data, leading to its constant use and high citation count (over 5000 citations in Google, 315 in Web of Science) [10:13:09] [11:07:09]. He affirms that the Nobel Prize, while it would have come eventually, would not have happened when it did without his work [00:21:09] [10:38:09].
Applications and Future Possibilities
The ability to generate and utilize attosecond pulses opens many unknown possibilities [00:32:09] [01:08:09], particularly for understanding the dynamics of complex molecules like biomolecules [04:11:09]. This technology enables cameras to operate at such incredibly fast timescales [12:45:09]. While the generated pulses are weak, they are strong enough to interact with inner electrons of atoms, allowing scientists to observe their dynamics [13:42:09].
One significant application of these short pulses is in medicine, specifically for cancer diagnostics [15:06:09]. High-frequency photons from attosecond pulses can penetrate molecules, characterizing their response to disturbances and potentially distinguishing cancer cells from non-cancerous ones [15:26:09] [17:06:09]. This research is conducted at facilities like the Extreme Light Infrastructure in Hungary, Prague, and Romania [14:43:09].
Quantum Computing and Machine Learning
Regarding quantum computers, Professor Lewenstein states that truly “error-tolerant” quantum computers do not yet exist [00:45:09] [17:35:09]. He clarifies that while prototypes exist, they currently offer no practical advantage over classical computers [17:53:09]. However, he highlights the significant development of quantum simulators (systems of cold atoms or ions) for simulating other physical systems, especially the dynamics of large quantum systems, where they demonstrate a “quantum advantage” [18:20:09]. Quantum communication, particularly cryptography, is also developing fantastically [19:08:09]. He reassures that quantum computers will not “take over the world” [19:34:09], as current advancements are more technical and important for technology and society, such as improving GPS accuracy through precise time and frequency measurement [19:40:09].
On the topic of quantum physics in machine learning, Professor Lewenstein acknowledges its potential but states that, as of now, there is no clear example of a “terrible advantage” of quantum machine learning over classical methods [20:30:09] [21:29:09]. It remains a very open problem [21:45:09].
Philosophical and Artistic Connections
Lewenstein delves into the philosophical question of “What is life?“. He discusses two main schools of thought:
- Mechanistic View: All living things are simply machines governed by rules, with no fundamental difference from inanimate matter [22:42:09].
- Emergence: Drawing from concepts of emergence, as seen in physics (e.g., magnetic ordering of spins at low temperatures), where a system with many simple elements and non-linear interactions gives rise to new, emergent qualities <a class=“yt=“yt-timestamp” data-t=“23:06:09”>[23:06:09]. Life, he suggests, can be imagined as an emergent phenomenon [23:58:09].
Lewenstein also shares a unique connection between quantum physics and Polish jazz music. As a collector of records, particularly free jazz, he wrote a book on Polish jazz in English [24:25:09]. Inspired by questions about randomness versus order in free improvisation, he and his colleagues created music using quantum random number generators, blurring the lines between art and science [25:28:09]. He encourages young Poles to pursue physics, despite it being a challenging career [26:14:09].