Why protective measurement does not establish the reality of the quantum state

“Protective measurement” refers to two related schemes for finding the expectation value of an observable without disturbing the state of a quantum system, given a single copy of the system that is subject to a “protecting” operation. There have been several claims that these schemes support interpreting the quantum state as an objective property of a single quantum system. Here we provide three counter-arguments, each of which we present in two versions tailored to the two different schemes. Our first argument shows that the same resources used in protective measurement can be used to reconstruct the quantum state in a different way via process tomography. Our second argument is based on exact analyses of special cases of protective measurement, and our final argument is to construct explicit “휓-epistemic” toy models for protective measurement, which strongly suggest that protective measurement does not imply the reality of the quantum state. The common theme of the three arguments is that almost all of the information comes from the “protection” operation rather than the quantum state of the system, and hence the schemes have no implications for the reality of the quantum state

Are the JCR impact factors of Indian S&T journals reliable?

26-30<span style="font-size:12.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa;="" mso-bidi-font-style:italic"="" lang="EN-US">Though SCI includes about 3000 S&T journals in its database every year, it does not show a good coverage of journals from the developing countries. In 1988 only 11 Indian -journals were covered in SCI This figure varies from year to year. The present study shows that the impact factors of Indian journals obtained from JCR are probably not true reflections of the quality of Indian journals.</span

Evaluation of growth of calcium phosphate ceramics on sintered Ti-Ca-P composites

Sintered Ti-Ca-P composites having in situ formed calcium phosphate phases developed by powder metallurgy processing were soaked for 28 days in simulated body fluid (SBF) with a pH of 7.4 at 37 degrees C and evaluated for the growth of calcium phosphate ceramics onto its surface. The composites were taken out once every 7 days and characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) for evaluating the Ca-P growth. Based oil the change in chemistry of the SBF and phase contents, a model has been proposed for mechanism of growth of calcium phosphate compounds on sintered Ti-Ca-P composites immersed in SBF. (c) 200

Corrosion Behavior of PM Processed Ti-Ca-P Bioceramic Composites in Hank's Balanced Salt Solution Using Potentiodynamic Studies

Ti-Ca-P bioceramic composites for load bearing implants developed by a new powder metallurgy processing technique were studied for their electrochemical corrosion properties. For determining corrosion behavior of such composites having in situ formed bioactive Ca-P phases, potentiodynamic and studies were conducted in simulated body fluid namely Hank's balanced salt solution. Potentiodynamic polarization tests showed no evidence of pitting corrosion. Corrosion potentials (-0.27 to -0.53 V) and corrosion rates (0.17-4.46 mills per year) of Ti-Ca-P bioceramic composite samples were superior to earlier reported results for coated Ti implants due to the formation of passive layer of bone-like calcium phosphate on the sample surface

Development of titanium based biocomposite by powder metallurgy processing with in situ forming of Ca-P phases

Composites of titanium and calcium-phosphorus phases were developed by powder metallurgy processing and evaluated for bioactivity. Titanium hydride powder and precursors of calcium and phosphorus in the form of calcium carbonate and di-ammonium hydrogen orthophosphate were mixed in different proportions, compacted and calcined in different atmospheres. The calcined compacts were subsequently crushed, recompacted and sintered in vacuum. In situ formation of bioactive phases like hydroxylapatite, tricalcium phosphate and calcium titanate during the calcination and sintering steps was studied using X-ray diffraction. The effect of calcination atmosphere on density, interconnected porosity, phase composition and modulus of rupture of sintered composites was examined. The sintered composites were immersed in simulated body fluid for 7 days to observe their in vitro behaviour with XRD and FTIR spectroscopic identification of deposits. Composites with 10 wt% precursors sintered from vacuum calcined powder gave the best results in terms of bioactive phases, density and strength. (c) 200

Fretting wear study on Ti-Ca-P biocomposite in dry and simulated body fluid

In the present work, powder metallurgy processing was used to synthesize a titanium rich composite containing in situ formed bioactive calcium-phosphatic phases. The potential application of such a composite includes load-bearing implants. In view of the importance of friction and wear in biomedical applications, the present work was taken up to investigate the friction and wear properties of such Ti-Ca-P composite at fretting contact against bearing steel in simulated body fluid (SBF) environment. A comparison was also made with fretting behaviour in dry conditions. Tribological experiments were carried out on a biocomposite against bearing steel at different loads (2, 5 and 10 N) for 10,000 cycles with displacement stroke set to 80 mu m and at 10Hz frequency using a low amplitude reciprocatory fretting wear tester. In addition to reporting the measured tribological data, a major focus of the work was in understanding dominant wear mechanisms under dry ambient and physiological environment. (c) 200