Notes by Akshat Jiwan Sharma

Electromagnetic wave propagation inside electron sheaths in a capacitive discharge plasma  ABSTRACT While the influence of plasma frequency on the propagation of electromagnetic (EM) waves has been extensively studied, the potential role of Lorentz force in perturbing free electrons in plasma sheath and thereby facilitating transmission of electromagnetic waves as per maxwell laws has received comparatively little attention. An oscillating EM wave at a frequency above the plasma frequency interacts with free electrons in the sheaths leading to generation of conduction currents. The frequency of oscillation of these conduction currents is equal to the applied wave frequency.  Although the primary EM wave propagates only a limited distance due to attenuation and geometric spreading, these free electrons carry the currents through the volume of the plasma making them detectable by probes placed deeper within the plasma body. This mechanism is similar to propagation of EM waves ...

7 Nov 2025 It was a great honor to participate in an online discussion organised by FT on the future of flight with technology leaders from Safran, Airbus,GE,and ONERA. As one of the biggest consumers of fossil fuels airlines have faced intense scrutiny that has led to several initiatives aimed at decarbonizing their operations. While electric flights are being explored as a possibility Hydrogen remains by far the most promising substitute for fossil fuels. Challenges remain around increasing its volumetric energy density through compression but that can be achieved through current compression technology. Given that hydrogen's energy density is about 3 times that of current fossil fuels a switch to hydrogen would cut the fuel use by a third enabling not just cost savings but also weight reduction. That is if green hydrogen could be produced reliably at scale. Engines are at the heart of any aircraft and I learnt from the speakers just how much effort is spent on the design of engin...

Construction industry has been trying to decarbonise but what materials can actually help it do that? It's a tough question.  Both concrete and steel almost seem indispensable.  Replacing steel is incredibly difficult in the construction industry.Some efforts have been made in substituting bamboo for steel.  Bamboo seems to offer a solution but bonding with concrete is a concern as many studies show & its true that hurdles remain even after a good bonding is achieved.  https://www.linkedin.com/posts/inbar-official_bamboo-reinforced-concrete-yes-or-no-bamboo-activity-7392199106464579584-c-W8?utm_source=share&utm_medium=member_android&rcm=ACoAAFNUr14BhT_6QYbNwdSgEVLcmX2XizbONxk But alternatives exist. One such proven technology is Mechanically stabalised earth in which soil is stabalised with horizontal grids to improve it's shear strength through friction.  Soil already has excellent compressive strength and by minimising its failure in shear it can ...

Research has been promising but skepticism remains due to the variable nature of lignocellulosic materials raising concerns about the reproducibility of carbon. Are plant based materials inherently unique in their chemical makeup that makes process control difficult? Many seem to believe so.  In lignocellulosic derived carbons what matters is the fraction of lignin,hemicellulose and cellulose in the mix. Different fractions will alter the composition of derived carbon / nanosheets slightly.  For example if a 130 day old peapod has higher lignin content it will have different characteristics than a 100 day old peapod.  So yes the results will be variable but they are not that hard to predict.  Example: Carbons derived from mature wheat straw (after crop is harvested) would have similar properties because wheat stops growing after a certain period. No more lignin or cellulose is deposited in the cell walls.  Same for jute ,coconut husk,flax  or sugarcane baga...

In his book do aliens speak physics physicist Daniel Whiteson asks thought provoking questions on the nature of reality and casts doubt on our current physical understanding of the universe.  What if our theories don't describe true reality? This is an important question to ask and one that has been asked by many philosophers. It forms the basis of ontology a branch of philosophy that deals with the nature of reality.  It is true that scientific theories describe a subset of reality and it's difficult to apply them outside of their domain. Particles physics can't predict hurricanes yet.  Aliens may choose different assumptions and come up with different theories. It would challenge our understanding of reality but won't change reality itself.   From a philosophical point of view it might be helpful to remove the foundations upon which our theories rest and see what remains. If you can get rid of that too then it's not fundamental. If you can't then it is. ...

  There is ongoing debate about the exact mechanisms that cause diamond formation in the microwave plasma chemical vapor deposition (MPCVD) process. While it’s well established that methane (CH4) and hydrogen (H2)are the key gases Hydrogen etches away non-diamond (sp2) carbon, while carbon from CH₄ contributes to diamond (sp3) growth.  Yet the exact carbon-containing species responsible for diamond growth ,whether CH3 radicals, C2 dimers, or other species are the dominant contributors are not known. It's also not clear what surface reactions and growth mechanisms contribute to growth and how these species attach to diamond surfaces and stabilize sp3 bonds. While the general scheme is agreed upon, the precise atomic and plasma-chemical pathways that make diamond grow in MPCVD[2] are still a topic of active research and debate. Here's what I think happens Hydrogenation of carbon structures adds H atoms to carbon.This process promotes sp3 hybridization in formerly sp2 ,sp carbons...