Bulletin of the American Physical Society
2016 Fall Meeting of the APS Prairie Section
Volume 61, Number 10
Thursday–Saturday, October 6–8, 2016; Northern Illinois University, DeKalb, Illinois
Session EE1: Poster Session |
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Chair: John Laubenstein, Charitable Management Systems, Inc. Room: Red Roof Inn, DeKalb, IL Lincoln Room |
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EE1.00001: Angular Size of 2cm Formaldehyde Emission in NGC 7538 Onic Islam Shuvo, Esteban D. Araya We present results of a work focused on measuring the angular size of 2 cm H$_2$CO emission in the high-mass star forming region NGC 7538 IRS 1. Our work is based on cross-scan mapping observations conducted with the NRAO 100m Green Bank Telescope, which were reported by Yuan, Araya and collaborators in 2011. The 2 cm H$_2$CO spectra show absorption superimposed with emission lines, thus, the emission and absorption profiles were fitted simultaneously to characterize the emission lines, and thus to measure the angular extent of the emitting cloud. We used East-West and North-South pointing positions of the cross-scan map to estimate the angular size of the source. Assuming Gaussian distributions on both directions, we found the deconvolved size (at half maximum) of the 2 cm emission equal to 52"$\pm$12". The angular size is important to determine the brightness temperature of the emission, which is needed to investigate the physical conditions of the gas based on a radiative transfer analysis of the 2 cm and 1 cm H$_2$CO lines. [Preview Abstract] |
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EE1.00002: Interlayer breathing and shear modes in NbSe2 atomic layers Zhipeng Ye, Gaihua Ye, Chun Hung Lui, Rui He Atomically thin transition metal dichalcogenide (TMD) niobium diselenide (NbSe2) has recently stimulated strong scientific interest due to its distinctive electronic and magnetic properties. We investigate the interlayer phonons of few-layer NbSe2 by ultralow-frequency Raman spectroscopy. We observe both the interlayer breathing modes and shear modes at frequencies below 40 cm-1 for samples of 2 to 15 layers. Their frequency, Raman activity, and environmental instability depend systematically on the layer number. In addition, the interlayer phonon modes evolve smoothly from T = 300 K to 8 K, with no observable response to the charge density wave formation in NbSe2. Our results are useful to understand the thickness-dependent properties of NbSe2. [Preview Abstract] |
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EE1.00003: Observation of Interlayer Phonons in Transition Metal Dichalcogenide Atomic Layers and Heterostructures Ye Gaihua, Zhipeng Ye, Chun Hung Lui, Rui He Interlayer phonon modes in atomically thin transition metal dichalcogenide (TMD) heterostructures were observed for the first time. We measured the low-frequency Raman response of MoS2/WSe2 and MoSe2/MoS2 heterobilayers. We discovered a distinctive Raman mode (30 - 35 cm-1) and identified this new Raman mode as the layer breathing mode (LBM) arising from the perpendicular vibration between the two TMD layers. We also investigated the ultralow-frequency Raman response of atomically thin ReS2, a special type of TMD with unique distorted 1T structure. We found that the two shear modes in bilayer ReS2 are nondegenerate and clearly resolved in the Raman spectrum, in contrast to the doubly degenerate shear modes in other two-dimensional materials. By carrying out comprehensive first-principles calculations, we can account for the frequency and Raman intensity of the interlayer modes and determine the stacking order in bilayer ReS2. [Preview Abstract] |
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EE1.00004: Reflectometry GUI: A MATLAB program for X-Ray reflectivity fitting and analysis Curt DeCaro, Laurence Lurio Reflectometry GUI is a program written for the MATLAB platform that provides multiple functionalities to analyze x-ray reflectivity data. The core function of the program takes a user-defined surface model, calculates the predicted x-ray reflectivity from the model, and fits it to measured reflectivity data by varying the parameters in the user-defined model. The user can define the material, thickness, roughness, and relative density of multiple layers in the model, and fit each independently or together to the measured data. The user can also define fit limits for each parameter. Materials are defined according to their chemical composition and bulk density. We hope that Reflectometry GUI will be a powerful analysis tool for modelling and fitting x-ray reflectivity data. It is intended to enable model analysis of complex, multi-layer surface systems. [Preview Abstract] |
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EE1.00005: Fluorescence studies of Sm $^{\mathbf{3+}}$\textbf{ and Sm}$^{\mathbf{3+}} \quad +$\textbf{Eu}$^{\mathbf{3+}}$\textbf{ co-doped bismuth telluro-borate glasses} Ting Chean Khoo, Panakkattu Babu, Saisudha Mallur Tellurite glasses doped with rare-earth ions are important materials for lasers and optical fibers. The telluro-borate glasses have high refractive index, good rare-earth ion solubility and excellent transparency in a wide wavelength range. The heavy metal bismuth oxide plays a significant role in enhancing the fluorescence of rare earth ions. The effect of tellurium content on the optical properties of Sm$^{3+}$ and Sm$^{3+}+$Eu$^{3+}$ doped bismuth telluro-borate glasses with the composition 30Bi$_{2}$O$_{3}$: (69.5-x)B$_{2}$O$_{3}$: xTeO2: 0.5Sm$_{2}$O$_{3}$ and 30Bi$_{2}$O$_{3}$: (69-x)B$_{2}$O$_{3}$: xTeO2: 0.5Sm$_{2}$O$_{3}$: 0.5Eu$_{2}$O$_{3}$ (x $=$ 10, 20, 30 mol{\%}) has been studied. The fluorescence spectra are obtained by exciting the glasses by a laser at 459 nm. Using radiative transition probability derived from the absorption spectrum of the sample, in conjunction with the fluorescence spectra, stimulated emission cross section for the intense band is calculated. The stimulated emission cross section is an important parameter in designing laser materials. The radiative transition probability and stimulated emission cross section are found to increase with increase in tellurium content. [Preview Abstract] |
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EE1.00006: Stimulated emission cross section and chromaticity study of Sm-doped bismuth telluro-borate glasses Suman Rijal, Saisudha Mallur, Panakkattu Babu Glass doped with rare earth (RE) ions are important materials for optical devices. We prepared a series of bismuth borate glasses with the composition xBi$_{2}$O$_{3}$:(99.5 - x) B$_{2}$O$_{3}$ (x $=$ 29.5 to 59.5 mol{\%}) doped with 0.5 mol{\%} Sm$_{2}$O$_{3}$ and studied the optical absorption and fluorescence spectra. Judd -- Ofelt (JO) theory is used to study the optical absorption and to calculate the radiative transition probabilities. We used area of the spectrum to calculate the oscillator strength. The set of the intensity parameters $\Omega_{t}$ (t$=$2,4,6)$_{\, }$is obtained from the experimental oscillator strengths and the calculated oscillator strength. $\Omega_{2\, }$parameter which depends on the asymmetry of the ligand field at the RE site and RE-O covalency is found to be maximum for the glass sample having 39.5 mol{\%} Bi$_{2}$O$_{3.}$ We calculated the stimulated emission cross-sections of the intense fluorescence lines of Sm$^{3+}$ ions. We used three glass samples with TeO$_{2}$ to study the chromaticity. The color coordinates corresponding to the prominent emissions of the glass samples were determined by using the CIE color matching function calculator. The color emissions were analyzed using the CIE color coordinate diagram. We got white color for all the samples except 30Bi$_{2}$O$_{3}$:20TeO$_{2}$: 59 B$_{2}$O$_{3}$:0.5Sm$_{2}$O$_{3}$ :0.5Eu$_{2}$O$_{3}$ which gave yellow. [Preview Abstract] |
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EE1.00007: Quantum size effects observed in high coverage Au layers on MoS$_{\mathrm{2}}$ Andrew Stollenwerk, Jacob Weber, Ryan Holzapfel, Keith Doore, Tim Kidd Scanning tunneling microscopy has been used to study the surface of Au thin films grown on MoS$_{\mathrm{2}}$ at room temperature using thermal evaporation. Immediately after deposition, the surface consists of terraced triangular structures with lateral dimensions on the order of 3-10 nm. After annealing to 600 K these structures condense into isolated terraced islands with lateral dimensions that reach 100 nm in some cases. Height distribution analysis after annealing indicates a preference for certain island heights corresponding to~N $=$ 8, 15, 23, and 29~atomic layers of Au. This result suggests that the growth mechanism is driven by quantum confinement considerations rather than strain effects. The preferred or "magic" heights correspond to those islands with states furthest from the Fermi level. Unlike observations of Pd and Ag films, the spacing of these peaks is consistent with the surface fermi wave vector rather than the bulk. [Preview Abstract] |
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EE1.00008: Thermodynamic Analysis of the Fullerene Nano Molecules Used in PDT(Photodynamic Therapy) Jun Suk Kim, Youjung Lee, Nikita Patel When advanced photoactive nanomaterials, such as functionalized fullerenes and carbon nanotubes(CNTs) contact Near Infrared Radiation (NIR), the resulting material behaves like a CNT nanobomb (CNT-NB), a key element in this cancer treatment. Treatment of cancer cells with CNTs with an antibody or substituted fullerenes and subsequent emission of NIR (700-1100 nm) result in the heating up of CNT-NBs. This heat is powerful, causing extermination of the body’s cancerous cells. Computational analysis of the unique structure of fullerenes and carbon nanotubes (CNTs) accounts for their high potential to be used as nanocarriers (NCs) in cancer therapy. As nanocarriers, the molecules’ distinct surface properties allow for enhanced function of absorption and/or bioconjugation of various moieties. In this paper, we used Avogadro to compare the safety and stability of the CNT and fullerenes, which are doped with various types of clusters, by checking their optimized molecular energy both stereochemically and thermodynamically. The software enabled us to calculate and determine optimized energy, determine the structural formulae, and model the electronic structures of the optimized molecules. [Preview Abstract] |
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EE1.00009: Challenges and Constraints in Designing a High Gain Single-Pass Amplifier for Optical Stochastic Cooling Matthew Andorf, Valeri Lebedev, Philippe Piot, Jinhao Ruan Optical Stochastic Cooling (OSC) is a proposed method to reduce the equilibrium energy spread and emittance of the beam in a particle accelerator. In OSC light generated in a pickup undulator is amplified and transported downstream to an identical kicker undulator. A magnetic bypass chicane between the pickup and kicker adjust the arrival time of each particle with its own radiation in such a way as to provide a corrective kick. The bypass chicane can only provide a few millimeters of optical delay for the amplification system and thus puts a strict constraint on the design. Fermilab is currently working towards a proof-of-principle OSC experiment with electrons at the Integrable Optics Test Accelerator (IOTA) that includes a passive test of OSC (no amplification) and an active test with an amplifier of 7 dB. For OSC to work in a hadron collider the amplifier gain must be increased to 20-30 dB, operate at a relatively large duty cycle of $\sim$ 1-10$\%$ and amplify pulses on the order of a few ns. Here we consider the challenges of reaching such high gains in a single pass amplifier with the above constraints. [Preview Abstract] |
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EE1.00010: First results from channeling radiation experiment at FAST Alex Halavanau, Philippe Piot, Jibong Hyun, Tanaji Sen, Wade Rush Channeling radiation is produced when an electron oscillates about a crystal plane. The radiation results from transitions between the quantum states normal to the crystal plane. We will present first results from channeling radiation experiment at Fermilab Accelerator Science and Technology (FAST) facility conducted in 2016. Many important challenges towards successful radiation generation experiments at FAST were studied and understood. We will focus on beam optics preparation, dark current studies and data acquisition system development. Finally, we will discuss the detector requirements and performance. [Preview Abstract] |
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EE1.00011: The First Particle-Based Proof of Principle Numerical Simulation of Electron Cooling Sumana Abeyratne, Bela Erdelyi Future particle accelerators require high luminosities in order to make precise measurements during collisions.~The proposed electron ion collider at JLAB (JLEIC) has targeted~an~ultra-high luminosity of 10$^{\mathrm{34}}$ cm$^{\mathrm{-2}}$s$^{\mathrm{-1}}$.~Reducing emittance growth is one key requirement to achieving high luminosity. Emittance growth is reduced by a process known as electron cooling, where a `cold' electron beam is co-propagated with a `hot' proton or ion beam in the cooling section of the accelerator.~~In order to estimate the cooling time accurately, the cooling force among particles needs to be precisely calculated. To this end, we have~developed a high performance computer code which allows to simulate electron cooling. Our code is the first particle-based simulation of electron cooling. In this work, we present the first results obtained that establish electron cooling of heavy ions.~ [Preview Abstract] |
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EE1.00012: Development of Radiation Hard Secondary Emission Sampling Modules Emrah Tiras, Kamuran Dilsiz, Hasan Ogul, David Southwick, Burak Bilki, Jane Nachtman, Yasar Onel Novel Secondary Emission (SE) sampling modules are introduced for high radiation environments. These new technologies could easily be used for the High-Luminosity LHC, future collider experiments, and lepton colliders. In this detector module, the secondary ionization mode was developed from the conventional PMT mode, and the first dynode is used as the active media as opposed to the photocathode. The SE electrons (SEe) are produced at the SE surface when charged hadronic and electromagnetic particles penetrate through an SE sampling module. The SE cathode is mostly made of metal-oxide and higher yield materials. These cathodes are used as secondary emission electrodes in conventional PMTs, which are used as the active media. Here, we report the physics motivation, the technical design of developed secondary emission modules, and characterization measurements of the both SE modes and PMTs. [Preview Abstract] |
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EE1.00013: Cholesterol Partitioning in Unilamellar Vesicles determined by Small Angle X-ray Scattering Preeti Vodnala, Jennifer Tournear, Soenke Seifert, Laurence Lurio, Elizabeth Gaillard, Kalyan Karumanchi Liposomes are artificial vesicles that are used for drug encapsulation and administration of pharmaceuticals or cellular nutrients. In this paper, small-angle x-ray scattering(SAXS) was used to study the structural properties of small unilamellar vesicles (SUV). In particular, we studied liposomes composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol bilayer. We examined the location of cholesterol by labelling cholesterol with bromine molecule. Lipid bilayer’s electron density profile has been modeled using a series of Gaussian shells and we reveal asymmetry within inner and outer lipid bilayer’s leaflet and that cholesterol is located one side of the leaflet adjusting itself to the curvature of a liposome. [Preview Abstract] |
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EE1.00014: Inkjet and Wax Printing: Low Cost Tools for High Throughput Sensors Madison Walton, Mohtashim Shamsi, Ahmad Zaman Qamar, Sensen Chen Inkjet and wax printing have recently become popular to fabricate devices for biosensing and bioanalytical applications due to need of low cost fabrication for resource limited regions of the world. Although inkjet and wax printing are commonly available technology, they have never been used in combination. We present here a rapid, low-cost and high throughput method to fabricate electrochemical sensors by combining inkjet and wax printing. Office-grade printers were used to print 96 electrochemical sensors per substrate in one hour for only {\$}0.03 per sensor. Electrochemical devices were printed on flexible polyethylene terephthalate (PET) substrate by using silver nanoparticle ink as a conductive layer and solid wax ink for a hydrophobic pattern as well as capping layer. Almost 96{\%} of printed devices were found to be functional on a single substrate. Sensors of various sizes and shapes can be printed simultaneously on one substrate and can also be customized on demand using a graphic design software. Depending on detection need, the conductive layer can be easily modified by electrochemical deposition of certain metals. Flexibility of these sensors holds potential for mass production by roll-to-roll printing. [Preview Abstract] |
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EE1.00015: Effects of Atmospheric Correction Aerosol Distribution Uncertainty on Hyperspectral Retrieval Error of Chlorophyll-a Colten Peterson, Raphael Kudela, Jesse Bausell Ocean color satellite and airborne sensors can accurately monitor chlorophyll-a (chl-a) using remote sensing reflectance (Rrs), but Rrs must first be corrected for optical perturbations caused by the atmosphere. Here, we conduct a sensitivity analysis of the 6SV atmospheric correction algorithm in order to gauge its performance in retrieving accurate chl-a measurements while systematically altering the algorithm's aerosol parameters. 6SV was run using an uncorrected L1 AVIRIS image of Monterey Bay where chl-a was sampled at three ocean stations. 6SV was initially run using the most accurate input parameters available, including a local aerosol optical depth measurement (AOD). Corrections were performed for all three sampling stations using all 5 6SV aerosol models, and the resulting Rrs values were converted into chl-a concentration using the SeaWiFS OC4 Algorithm. AOD was altered iteratively in order to determine the effect on chl-a retrieval error. Results indicate that overestimating AOD leads to much higher error in chl-a retrieval as compared to underestimation. Out of the 5 6SV aerosol models, the coastal model produced the most accurate chl-a values. [Preview Abstract] |
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EE1.00016: Stereo-Chemical and Computational Analysis of Luminol Molecule and its Isomers Using Quantum Physical Energy Jae Eun Kim, Dayeon Cheong, Sewon Cindy Park Luminol, efficiently used in the field of forensic, medicine, and plant sciences, detects bloodstains at crime scenes and develops biosensors. This research provides theoretical and computational analysis of the luminol molecule and its derivatives. The computational analysis and calculations of optimized energies(kcal/mol) of Luminol's derivatives, which have large role in molecules’ stability, were carried out based on the electronic density functional analysis. The stabilities based on optimized energies of the conformations of luminol tautomers were presented and the comparisons of the numerical data with the original luminol are given. Through the analysis of stability order, we can confirm the use of electronic density analysis as functional. Also the study confirms the existence of three important factors that influence the relative stability of luminol's tautomers. The first factor is the aromaticity and electronic delocalization, which depends on the number of molecular orbitals of p character. The second is the molecule's hydrogen bonding and the third, and the most important factor, is charge distribution. [Preview Abstract] |
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EE1.00017: Study of Transcription Factor- DNA interaction using AFM Khdr Eskandar, Mohannad Ahmad, Ashwani Kumar, Laura Moore This research aims to determine the characteristics of transcription factor binding to DNA using Atomic Force Microscopy. Atomic Force Microscopy (AFM) is an instrument that scans extremely fine surface features to create three-dimensional images. AFM can also be used to measure the binding force between a protein anchored on a solid support and a small molecule attached to the AFM tip In this study, we are examining, CRP, a transcription factor found in \textit{E coli,} and its association with known CRP promoter regions in the DNA. CRP protein with T8C mutation was isolated using His tag purification method. The cysteine mutation in the 8$^{\mathrm{th}}$ position of the primary structure of the protein will be used to attach CRP to an ultra-flat gold surface through a thiol bond. This technique results in the formation of a CRP monolayer, which allows us to image the protein and perform force measurements. Segments of DNA that contain the promoter region for CRP were amplified by PCR reaction from chromosomal DNA of E. coli bacteria strain W3110, imaged and analyzed by ezAFM. Future work will include attaching this promoter region to the AFM tip and measuring the binding for between the CRP on the solid support and the DNA on the tip. [Preview Abstract] |
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EE1.00018: Remote Sensing of Electical Currents in Astrophysical Plasmas Steven Spangler Galvanometry is usually considered a local lab measurement carried out with electrical circuits. Electrical currents must flow in astrophysical plasmas like the solar corona, the interstellar medium, and the plasma ``atmospheres'' of clusters of galaxies (intracluster media), but it would seem to be nearly impossible to measure them. Remote measurements of electrical currents in astrophysical plasmas are possible, using observations of Faraday rotation with a radio telescope such as the Very Large Array. Faraday rotation is a rotation in the plane of polarization of a linearly polarized electromagnetic wave due to propagation through a ionized gas with a magnetic field. Differential Faraday rotation, or the difference in the Faraday rotation between two adjacent lines of sight, gives a quantity which is very close to the integral in Ampere's Law (Spangler, Astrophysical Journal 670, 841, 2007). Application of this technique to observations through the solar corona yields currents as high as 2.5 Giga-Amperes flowing in an Amperian Loop with sides separated by 33,000 km. I will discuss the extension of this technique to other astrophysical plasmas that can be probed by the Very Large Array. [Preview Abstract] |
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EE1.00019: A Study of 6.7 GHz Methanol Absorption in the Galaxy Wei Siang Tan, Esteban D. Araya One of the most prominent masers found in regions of high-mass star formation is the 6.7GHz transition of methanol. This line has been detected in emission towards hundreds of sources, however detection of 6.7GHz methanol absorption is far less common. We discuss detection of 6.7GHz methanol absorption towards G45.12+0.13, a high-mass star-forming region observed with the Arecibo Telescope in Puerto Rico. We also present results of a complete literature review of 6.7GHz methanol absorption. A total of 30 regions have been reported to show 6.7GHz methanol absorption; in most cases, the absorption is likely against compact radio continuum sources. In only 2 cases the absorption must be against the Cosmic Microwave Background, which indicates that the transition can be anti-inverted. Our study shows that 6.7GHz methanol absorption mostly traces active high-mass star forming regions, based on detection of HII regions and relatively large spectral line-widths, which are indicative of turbulent environments. Even though some blind high-sensitivity surveys have been done, the sensitivity of most studies was optimized for the detection of masers and not weak absorption features, thus a population of weak 6.7GHz methanol absorbers below the ~100mJy level may be present. [Preview Abstract] |
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EE1.00020: ECG Measurement with NI myDAQ Ziwei Jiang, Yumin Zhang The ECG signals are collected from both arms, with one leg engaged as the ground reference. The first section has first order RC low pass filters, and the cutoff frequencies for the common and differential modes are 500 Hz and 10 kHz, respectively. These filters can remove the high frequency noise significantly. The second section is an amplifier, and the gain is set to 100 V/V. The third section is a first order RC high pass filter with the cutoff frequency at 0.5 Hz, which can remove the low frequency interferences. The fourth section is the second stage amplifier and its gain is set to 20 V/V. The fifth section is a notch filter, and it is used to remove the 60 Hz AC interference. There are five main sections in the DAQ circuit: DAQmx virtual channel, DAQmx timing, DAQmx start, DAQmx read and DAQmx stop. With virtual channel template, the physical channel and the input type/range are set. The analog voltage input channel with the sampling rate at 500 is used. The number of samples per channel is set at 1000. In order to further suppress the 60 Hz interference, we put a 3rd order Butterworth IIR band stop filter with the cutoff frequencies at 55 Hz and 65 Hz, respectively. [Preview Abstract] |
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EE1.00021: Communication and Process of a Package of Information by Photon, Faster than Light Speed in Link's Point of two Planck Lengths Hassan Gholibeigian, Abdolazim Amirshahkarami, Ghasem Gholibeigian, Kazem Gholibeigian In our vision, there in dimension of information in the universe which is nested with space-time. A photon needs to communicate and process a package of information including its exact quantum state and necessary governing equation for travelling a Planck length. This fast process should be done by photon in a link point of two Planck lengths. The photon can't stop between two Planck lengths and spend time for processing. Consequently, this process should be done faster than light speed. By using the proposed formula for number of packages of information ($I)$: $I=t_{P}^{-1} .$ $\tau$ In which $t_{P} $ is Planck time and $\tau $ is lifetime of fundamental particle (string) per second, we can see that a photon processes $1.8\times 10^{43}$ packages of information in speed of faster than light speed for finding its 300000 km path in a second. This is the programming of the electromagnetic fields by photons via information dimension in the universe. [Preview Abstract] |
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EE1.00022: Communication and Process of a Package of Information (CPPI) by the Fundamental Particle (String) in a Planck Time as the "Fundamental Physical Constant'' in Nature Hassan Gholibeigian Fundamental particle (string) needs a package of information including quantum information of its exact position and law for motion to its next step, which is a Planck length or going to the next situation which is occurred in a Planck time. On the other hand, this process is including two stages as follows: 1- communication of information via its sub-particles (substrings) from dimension of information which can as the ``fundamental Symmetry'' in the nature, 2- processing the information (a symmetry in nature), while it is interacting with its neighbors, and moves to its next situation. So, it is necessary that a package of information be near each of fundamental particle. In other words, dimension of information including new packages is nested with space-time, and its densities in its different locations are matched on correspondence densities in space-time. So, black hole's location including most density of packages in nature. My proposed formula for number of packages of information ($I)$ is: $I=t_{P}^{-1} .\tau $ in which $t_{P} $ is Planck time and $\tau $ is lifetime of fundamental particle (string) per second. Therefore, I propose CPPI as a ``fundamental physical constant'' in nature. [Preview Abstract] |
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